Talk:AVCHD

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Partial ?

The item ""Pioneer BDP-51FD"" in table "Blu-ray Disc players known to play AVCHD discs" contains Partial when reffered to playback of FullHD. Please note that even you give the refference for a claim, you won`t make Pioneer bdp51fd play whatever you want. I can`t figure out how on earth could you not tag "Partial" as original research 188.25.49.107 (talk) 11:19, 19 July 2011 (UTC)

File format

There is no mention of time code in the AVCHD article. Does anyone know how to edit the original time code and date information that is embedded in the metadata of an AVCHD file?

Maybe something should be mentioned about how this compares to M-JPEG which is a non-temporal compression.

Intent/purpose of listing individual camcorder models in the main article

I'd like to understand the reasoning behind the product-listing. Is the article attempting to serve as a product guide? Because if it is, then it's incomplete, confusing, and largely irrelevant to communicating the meaning and overview of AVCHD. The Panasonic section includes some digital still cameras with AVCHD-lite, but the GH1 can capture at 1080/24p (which is beyond AVCHD-Lite)? But that's beside the point, it makes absolutely no organizational sense to create a combined listing of CONSUMER-grade digital-cameras (which are arguably tertiary video-recorders), consumer camcorders, and professional/industrial camcorders (Panasonic HMC.) Not a single-reader will search for that mix of info, and it just clutters the article with expirable-trivia (i.e. obsolete when next-year's product-line.)

Overall, the product-listing section only makes sense if it somehow conveys useful information (beyond just a listing.) If the product-listing is to stay, it needs to be carefully re-organized and trimmed into something that adds content to the article, not just filler. For example, if the reader can get a sense of "30% of camcorder product SKUS are AVCHD, such as the following...", or "in 2008, 15% of consumer camcorder revenue came from camcorders offering AVCHD product", or "AVCHD has become more popular in camcoders, but increasingly camcorders are being overlooked as less-expensive digital still cameras offer a comparable (H264) movie-mode." (<-- Hypothetical examples only! Not assertions of fact!) Or if a particular model is noteworthy/unique from its peers (i.e. the GH1 combo-camera being the first consumer-level product with AVCHD @ 720p50/720p60, not including the TZ7/ZS3 which simply store 720p30 video in a 720p60 bitstream.) The way the products are listed now, it's a just a clutter of undifferentiated model#s (which, by the way, isn't helped by the different model#s used for USA vs European markets.) —Preceding unsigned comment added by 99.60.52.54 (talk) 03:32, 3 August 2009 (UTC)

I think that the product list does not hurt. At the very least it shows the breadth of the market, the number of the models, the timeline. It is also a placeholder for references into manufacturers' press releases, which often contain useful information besides usual marketing fluff.
I don't think that consumer/pro camcorders should be separated. Manufacturers want to separate these markets because they charge more for pro models, but for us as consumers this separation does nothing good, it is artificial.
Adding information about notable features would not hurt, but it should be kept compact and concise, otherwise the product list will dwarf the main article. Another way of mentioning notable features is to create article for a particular model that stands out. This is what I did for the SD1, SD100, HMC150 and the HMC40. Go on, create a page for the GH1 if you like, and link to it. Mikus (talk) 19:41, 4 August 2009 (UTC)

Resolution

Is there an implied resolution with the AVCHD format? For example we know that in HDV it is going to be either 1440x1080 or 1280x720. Is there a predefined resolution and aspect ratio for AVCHD? Also what about pixel aspect ratio - are they square of rectangular? Peel 22:09, 28 June 2007 (UTC)

There is more to the resolution than pixel-count such as Compression Artefacts. Lower bitrate = more artefacts = worse image. In fact, higher the pixel count higher the compression to fit it into the max. 28 Mbit/sec datarate. (This was already observable on the Sony FX1: the standard DV image looked visibly better than the HD image.) With the max 28Mb AVCHD is pretty low quality. Regarding the pixel-count the question is referring to, the format allows them. Real-life support is another matter. Check out the actual camera.

Also, whether this format support 1080p or just 1080i? Does the camerca currently support only the interlace format? What about the use of the format in professional area? or this just for home user? --WikiCantona 07:57, 1 September 2007 (UTC)

Progressive video comes in two formats: single or dual 'frequency'. IE:720p25, 720p50; 1080p25, 1080p50 and naturally the NTSC equivalents plus the so called 'film-format' that is 24p. Today all of them are supported by the standard. The actual camera is a different matter.
True progressive formats are supported. AFAIK, Panasonic SD9 can record true 24p unlike Canon camcorders, which record telecined 24p-in-60i video. —Preceding unsigned comment added by Mikus (talkcontribs) 01:20, 22 May 2008 (UTC)
  • The HDC-HS100 and HDC-SD100 have only 1080i according to the (German) user manual. Maybe there are differences between US/Europe/Japan?
I don't know about European versions, but I can assure you that 60Hz version of the HS100/SD100 records true 24p. I am a bit puzzled reading about HS300/TM300 on Panasonic's own website that these camcorders record 24p-over-60i. I think this is misinformation, I don't see why Panasonic would revert from true 24p to 24p-over-60i. Mikus (talk) 07:20, 9 March 2009 (UTC)

Neither HDC-SD9/HDC-SD9 nor HDC-HS100/HDC-SD100 models are capable of recording native 1080p24 video. When these camcorders were announced by Panasonic in early 2008, the specifications promised 1080/24p. However, the actual retail models that arrived on the market in the ensuing months did not meat specification. All UPDATED sources either state 1080i as the highest recording quality or simply say "1920 x 1080" without specifying i or p because most consumers wouldn't know the difference anyway. Panasonic clearly failed to deliver on its promises. That's the reason for the abundance of misleading information about these products. If you do your research carefully, you'll eventually come to this realization: No consumer camcorder on the market today using AVCHD is capable of capturing native 1080p video. BDS2006 (talk) 07:02, 14 June 2009 (UTC)

If you indeed research carefully you will find out that the "9" and the "100" do record native 1080p24. I have the SD100 myself. If you want I can send you the MTS file. Mikus (talk) 17:50, 15 June 2009 (UTC)
If you indeed research carefully you will find out that the "9" and the "100" do not record native 1080p24 if you purchased the camera anywhere other than in the US or Japan. 50 Hz versions of those cameras can only record in 25 frame "progressive" and then only using progressive segmented frame (which isn't really a progressive format but an interlaced format where both fields are taken at the same moment in time). Even then only in conjunction with x.v.color, which most TVs do not support. 109.157.161.93 (talk) 16:50, 6 December 2011 (UTC)

Recording AVCHD on standard DVD vs. Dual Layer DVD

Can someone with some knowledge on the subject tell me if you can record AVCHD format on a standard DVD-R or Mini DVD-R? I recently bought a new HD DVD Video Camera and I was told by the sales clerk that in order to "record/playback" in the full 1080i HD quality that the camera offers that I need to use a Dual Layer Mini DVD as opposed to a standard mini DVD (1.4Mp)

I understand there will be a difference in the amount of "time" I can record on a standard DVD vs. DL DVD... I'm not concerned about that... I'm strictly concerned about getting HD quality out of a standard DVD... Does it have to be Dual Layer??

No, it does not have to be Dual Layer. The clerk did not know what he was talking about. Mikus (talk) —Preceding comment was added at 01:19, 22 May 2008 (UTC)

Article Name

The article has recently been renamed Advanced Video Codec High Definition. It is correct, but it is more commonly addressed as AVCHD. The HDV article is not called High Definition Video. Or is that because there is already an article called High Definition Video? —Preceding unsigned comment added by Wuffyz (talkcontribs) 13:15, 1 October 2007 (UTC)

Moved to AVCHD. Mikus (talk) —Preceding comment was added at 01:17, 22 May 2008 (UTC)
I think "Advanced Video Codec High Definition" may interest some people too.188.25.49.107 (talk) 11:21, 19 July 2011 (UTC)

Linux compatibility

As of yet, there are no all-in-one programs to edit AVCHD video. However, there are scripts that utilize multiple programs to convert AVCHD video to video formats that can be edited with Linux programs. The question is, can one of these conversion scripts be listed as a program under "Software that converts the AVCHD format to other formats"? Case in point: m2tstoavi

CompIsMyRx (talk) 21:48, 5 January 2008 (UTC)

Don't mix file format and support

"Among the touted advantages of AVCHD over MiniDV tapes is random access," copied from the article is plain stupid. AVCHD is a file format and could as well be copied to mini DV tape.

Compare AVCHD and mpg2 video on dvd if you want... —Preceding unsigned comment added by 82.228.87.93 (talk) 14:45, 5 May 2008 (UTC)

Clarification on the Overview section

from the article "AVCHD supports a variety of resolutions and aspect ratios, all the way from 480/60i to 1080/60i "Full HD" with 1920x1080 pixels in 16:9 aspect ratio"

Full HD everywhere I've looked is called 1080p, 1080i is only the 'maximum' resolution of broadcast television, the specification for HDTV is very clear that 1080i is not the full capability of high definition TV(as a matter of fact 2160p is going to roll out in 2015, so now even 1080p isn't reall 'full hd' anymore, on paper at least). so if 1080/60i is the maximum resolution of AVCHD it shouldn't use the phrase 'Full HD' as it is not 1080/60p that is the standard resolution 'associated' with the phrase "Full HD" today.

frankly i think the words 'full hd' should be taken out, it's not the maximum resolution of HD content available today, and it's not even close to the maximum resolution in 2015 if anyone bothers supporting 2160p. Kesuki (talk) 20:58, 2 June 2008 (UTC)

Full HD is not a technical term, so I removed it along with other bla-bla. See spec table at the end of the article for supported resolutions and rates. Mikus (talk)

Bot report : Found duplicate references !

In the last revision I edited, I found duplicate named references, i.e. references sharing the same name, but not having the same content. Please check them, as I am not able to fix them automatically :)

  • "BackingUpAVCHD" :
    • {{cite web | url=http://www.elurauser.com/articles/avchd_to_bluray.jsp | title=Backing up AVCHD video onto DVDs and playing them on a Blu-ray player | publisher = elurauser.com }}
    • {{cite web|url=http://www.elurauser.com/articles/avchd_to_bluray.jsp|title=Backing up AVCHD video onto DVDs and playing them on a Blu-ray player}}

DumZiBoT (talk) 01:03, 12 August 2008 (UTC)

Please give us a link for duplicate refferences in wikipedia.org. I have an interest to find out if websites with no forma of contact have priority ranks over some older ones. More exactly, the http://www.elurauser.com/articles/avchd_to_bluray.jsp has no contact for webmaster details. Should not a journal|newspaper website stand refference for anonymous posts in forums? Where is claimer authority in your website ?

188.25.49.107 (talk) 11:30, 19 July 2011 (UTC)

Merge from .m2ts Notes

I've Been Bold, and merged .m2ts into AVCHD, as ".m2ts" is merely the typical filename extension of AVCHD files on a computer.

I set the old .m2ts page to redirect to the "Software" section of AVCHD, as if a user is wondering what this strange file is, they're likely more interested in finding out what it is, and how they can open it, rather than trying to sort through a long, detailed article on the encoding format used in the file.

I've done a decent amount of reformatting, but a bit more cleanup might be necessary, as I already saw a "playing" section in this article, which barely deals with the software required for personal computer playback. There's also some unverified information, potential link spam, and some possibly obsolete data. MinstrelOfC (talk) 01:58, 10 February 2009 (UTC)

And... it's been reverted - poorly. The data from the old .m2ts article is gone, the redirects are pointing to the wrong place, the talk page (here) now has a fallacious header, and there's no note on the "Software" section header that something links there.
I don't have the time to fight over, or otherwise deal with this, so if some awesome editor could take a look, that would be cool.
From the 10 words Mikus said, I think he's implying that the data from .m2ts should be moved into MPEG_transport_stream instead.
Good Luck.
MinstrelOfC (talk) 10:49, 10 February 2009 (UTC)
M2TS is not a codec format, it is a transport format. It can contain anything, MPEG-2 or MPEG-4 or something else. Therefore, AVCHD article is not a place to discuss M2TS details. There is a separate article about MPEG-2 transport stream. Mikus (talk) 07:22, 9 March 2009 (UTC)

Converting

"Nero Vision can convert AVCHD files to other formats such as MPEG-2 or AVI and can import them for use in video editing projects."

Maybe this is just nitpicking, but AVI is a container format while MPEG-2 is a compression standard. So converting to AVI is not all that clear. Does this mean re-muxing into an AVI container (not a good idea for H.264) or re-encoding into a different compression format? And which compression format, as AVI can contain pretty much anything.

Can you provide me some details for statement re-muxing into an AVI container (not a good idea for H.264?, thank you188.25.49.107 (talk) 11:32, 19 July 2011 (UTC)

Acronym

Even though the web site doesn't spell it out we can inform the readers what it stands for. Daniel.Cardenas (talk) 18:32, 9 March 2009 (UTC)

There are tons of other references that indicate what it means, just do a google search. It maybe in one of the docs that are available from the consortium, but not available to the general public. Daniel.Cardenas (talk) 18:43, 9 March 2009 (UTC)

Per wp:lead the lead paragraph should contain the most pertinent info. Daniel.Cardenas (talk) 15:18, 10 March 2009 (UTC)

Keep in mind that wikipedia is not an extension of a consortium's web site. Wikipedia's has its on policies, guidelines, and goals, such as to provide a balanced perspective. Daniel.Cardenas (talk) 16:06, 10 March 2009 (UTC)
Reverted. There is no indication that AVCHD is an acronim. It most likely is, and anyone can make a reasonable guess that it possibly stays for AVC-HD, and AVC stays for advanced video coding, and HD stays for high definition. But this is not a 100% verified encyclopedic information, because AVCHD founders have never spelled this as acronim. So treat it as a five-letter name. By the way, there is a link to AVC/H.264 page, and AVC is spelled out there. Anyone who is interested what AVCHD is about can click a link. Also, AVCHD has provisions for SD video as well. It is not implemented in known camcorders, but nevertheless AVCHD supports SD video, therefore spelling it out as AVC high definition will not be entirely correct.Mikus (talk) 00:39, 11 March 2009 (UTC)
In regards to AVCHD being based on H.264, this is stated in the very first sentence of the overview. There is no need of littering the article intro with non-sensical information. Those who are interested in tapeless high def video will read on and will find all information needed, either directly or via links. Remember, that internet in general and wikipedia in particular are about links. Do not increase the entropy.Mikus (talk) 00:39, 11 March 2009 (UTC)
Neither HDV, nor DVCPro nor XDCAM nor multitude of other recording standards are spelled out as acronyms. This is just a label, a name, treat it as such.Mikus (talk) 00:40, 11 March 2009 (UTC)
Maybe I'm daft, but I went to this page to figure out what the letters stand for. Whether it's a 'name' or an acronym is a totally theoretical discussion - this specific letter combination wasn't chosen for fun, it was chosen with a purpose. If the meaning isn't clear, or ambiguous, it can be stated as such, but leaving this information out completely makes no sense to me. KryzMasta (talk) 13:36, 11 March 2009 (UTC)
I would say the opposite: whether this letter combination had been chosen for fun or for a purpose is a totally theoretical question. All we need to know what the name stands for, and this is tapeless HD recording standard, end of story. One can make theories about what these letters stand for, but this is not important. These five letters are a unique label that define a specific thing, that is it. There is no explanation what HDV stands for. Or XDCAM. Or XDCAM HD (HD probably stands for high definition, so what?). Or XDCAM EX, what EX stands for? EXtended? EXpanded? EXpress card? Or DVCPro, are you going to dissect the name and make assumptions that DVC supposedly stays for Digital Video Cassette, this was the original name for DV, and Pro stands for Professional? Probably, but this is not important. What people need to know is what standard a video has been recorded in, that is all. This information is sufficient to work with it. If you are interested in history, click on AVC/H.264 link and read on. That article, by the way, spells out AVC acronym, I don't know is it correct or now, but I don't care. What does VC-1 mean? What does MPEG-4 mean and is it two versions above MPEG-2? (Not really, MPEG-3 never happened, MPEG-5 and MPEG-7 are some totally different things, the numbers are not comparable). What does Betacam SX mean? Yeah, these names surely have some remote meaning buried in them, but people treat them as labels, because this is what they are, and two names having common parts do not imply that the respective video standards are compatible. Mikus (talk) 19:27, 11 March 2009 (UTC)
You're forgetting the point of Wikipedia: to relate information to those who look for it. Whether you think there is a meaning to these letters or not, and whether you think this meaning might be important, does not matter. ANY term on Wikipedia is explained (look for example at agnosticism - does it matter for the meaning what the heritage of the word is? no, because there's a definition that superseeds any meaning). Thus, the heritage of this term should also be explained. If it's not 100% verifiable, then make that clear. The simple fact remains: I came looking for what the letters stand for, and I didn't find it here. Whether it means something or not is totally irrelevant. KryzMasta (talk) 10:45, 13 March 2009 (UTC)
> I came looking for what the letters stand for, and I didn't find it here.
The letters stand for a consumer tapeless HD video recording standard. Mikus (talk) 07:48, 15 March 2009 (UTC)

>There is no indication that AVCHD is an acronim.

Added a reference. There are many more indications if you'd like.
shedworx? Are they member of AVCHD consortium? You could as well link to your own blog. As I explained above, all other formats are listed as they are, neither HDV, nor XDCAM, nor DVCPro nor mutitude of others are spelled out. AVCHD is no different, it is just a name. Mikus (talk) 17:57, 12 March 2009 (UTC)

>But this is not a 100% verified encyclopedic information

This is not the standard for entry into wikipedia. The standard is verifiable, not truth.

>In regards to AVCHD being based on H.264, this is stated in the very first sentence of the overview. There is no need of littering the article intro with non-sensical information.

Are you saying that the first sentence of the overview has nonsensical information? Do you know what wikipedia policy is for what goes into the lead paragraph? Read it: wp:lead.
Bad choice of words. I meant, that this link is given below in overview, no need to litter the intro. Mikus (talk) 17:57, 12 March 2009 (UTC)

>... and wikipedia in particular are about links.

I don't understand what you are trying to point out. Most wikipedians would not say that wikipedia is about links. Daniel.Cardenas (talk) 01:01, 12 March 2009 (UTC)
Internet is about links. No need to duplicate information if you can click a link and read it elsewhere, on its source site. This article links to AVC/H.264 article in the very first portion of an overview, this is enough. Anyone who got interested enough to get to overview is able to click that link. Mikus (talk) 17:57, 12 March 2009 (UTC)

I added more references to address the issue about shedworx. User Mikus has reverted the changes to make the intro conform to wp:lead with out explanation, except to call it litter. Please correct my assessment if incorrect. I've also requested 3rd part opinion in this dispute. http://en.wikipedia.org/wiki/Wikipedia:Third_opinion#Active_disagreements   Daniel.Cardenas (talk) 19:12, 15 March 2009 (UTC)

I already explained my arguments above for several times, I could not explain them better, but I can repeat them in case someone is still not getting them. (1) Articles about video standards do not spell out the names, and the names are not treated as acronims, they are treated as unique combination of letters to identify a product. (2) Even if this is an acronym, there is no official spelling of it, the best we can do is guessing, and wikipedia is not about guessing, it is about facts. (3) Information that you keep adding to the heading, is already presented elsewhere in the article. There are links to AVC/H.264 page, to MPEG transport stream page and to AC3 page. This is enough to steer a curious reader to the right source. I believe that the heading should be as short and concise as possible and should not throw all available information onto a reader. Mikus (talk) 18:49, 19 March 2009 (UTC)

Does your belief agree with wikipedia policy about what goes into the intro: wp:lead? Specifically the intro should be a concise summary indicating the most interesting or pertinent points. Daniel.Cardenas (talk) 18:40, 20 March 2009 (UTC)
Per wp:lead, "It is even more important here than for the rest of the article that the text be accessible. ... In general, specialized terminology should be avoided in an introduction." You, on the other hand, inserted three buzzwords and an unofficial initialism. "For example, rather than giving the latitude and longitude of a town, it is better to state that it is the suburb of some city." Translated to the subject, rather than bombarding an unprepared user with buzzwords, it is better to state what AVCHD is about, that is, about high-def consumer videography. "Significant information should not appear in the lead if it is not covered in the remainder of the article." -- this is exactly what the lead looked like before you decided to change it. All information that you stuck into it is discussed/linked further in the article. "Leads are usually written at a greater level of generality than the body, and information in the lead section of non-controversial subjects is less likely to be challenged and less likely to require a source." -- Which means that you better remove your "abbreviation" to avoid confrontation. I don't know why I am trying to explain this to you, because you did not seem to read what I wrote above. NO OTHER video standards are spelled out, got it? Mikus (talk) 00:45, 21 March 2009 (UTC)
4 people believe the initialism should be there and one doesn't. Got it? Daniel.Cardenas (talk) 03:39, 21 March 2009 (UTC)

Just to pour petrol on the flames. I have found a reference that seems to predate the citation given ion the article. It is from Panasonic (same as the source in the article). It is in the pre-release literature for the HDC-SD1 camcorder (dated 2007) which claims that it stands for "Advanced Video Capture High Definition". Rather interesting, I think. I have no intention of modifying the article on the basis of this reference, because expansion given does seem to be more prevalent. However, I believe, the expansion came after the acronym. DieSwartzPunkt (talk) 17:16, 17 April 2011 (UTC)

Is not it funny that just like HDV, AVCHD has standard def mode. Mikus (talk) 05:37, 4 December 2011 (UTC)
Yes indeedy: the AVCHD codec does have standard definition support. However, the HDV system does not have a corresponding standard definition mode. The standard definition system that I believe you are thinking of is just plain DV. They are not the same (apart from the tape) as they use completely different compression systems (codecs). HD is spatially compressed only. HDV is both spatially and temporally compressed. DieSwartzPunkt (talk) 14:18, 5 December 2011 (UTC)

3rd opinion

This comes to you from 3rd opinion requests, but IS simply an outside opinion, not an entry into the argument. I hope it helps; I can be contacted at my page, but I have not taken the notice down at 3O.

It is reasonable to wonder whether the term is an acronym, how it is pronounced and what it means, so Wiki should deal with it, using sound secondary sources. The prospectus from the makers is a primary source. Both points of view need to find their best, most authoritative and verifiable secondary source dealing with this explicitly. If there are notable sources stating both views, include both. If only one, include only that. If there are NO known notable statements on the matter, insert this information editorially. But it is not right to ignore the question, and the statement that the term is not an acronym, while negative, DOES require a citation. Useful information that fits inclusion criteria cannot be excluded because it is available elsewhere. Wiki is made up only - or should be - of such information. Thanks Redheylin (talk) 16:32, 18 March 2009 (UTC)

I read the dispute too as it was NOT removed from the 3rd opinion page. I would generally agree with Redheylin. I will add that without any knowledge on the subject it seems intuitively to me that this acronym is accurate. However, if is unofficial, that should be made be clear and cited. As the article is currently presented, it is presented definitely as an acronym which based on the discussion seems inaccurate (the sources that use it as an acronym could be better as well). Try to convey both its meaning and its official nature if it is not officially an acronym. Wikipediatoperfection (talk) 00:46, 19 March 2009 (UTC)

(cur) (prev) 19:12, 15 April 2009 Mikus (talk | contribs) (31,631 bytes) (AVCHD uses AVC only) (undo)

If that is the case, why am I able to create an AVCHD that contains MPEG2 data and plays on my PS3? —Preceding unsigned comment added by 83.245.110.2 (talk) 14:36, 16 April 2009 (UTC)

This is a non-standard format, and PS3 is very flexible. Non-standard formats may work on some (or on many) players, but they are still non-standard formats, period. Mikus (talk) 17:45, 15 June 2009 (UTC)
Also see AVCREC Mikus (talk) 19:30, 4 August 2009 (UTC)

Use of terms "true progressive and true 720p" pejorative

While 720p 59.94 fps may be the current US broadcast standard for 720p HD content, AVCHD allows for other frame rates. Using the terms "true progressive" and "true 720p" is pejorative and should be avoided. Progressive means the frame is not broken into interlaced fields, so while Panasonic's AVCHD lite 29.97 progressive frames doubled to 59.94 frames per second may not be US broadcast standard 720p, it is progressive format frames, and 1280 by 720. ShumDavar (talk) 15:21, 7 December 2009 (UTC)

if it`s a progressive stream than it`s 1280 by 720p. Format is not "stream framing".
Pretty much each of us can differenciate 720p to progressive and to double 29.97 to 59.94.
I don`t see why would you preffer sayin` true progressive and let me not know of research for hdtv "720p" that is a more on the subject relating to "high definition". You may find 720p down the botton of the article. To censor out 720number and say "true progressive" it`s like wikipedia clear out refferences describing new digital technologies available to US consumer. Redundancy may be good because user clicks away to new technologies like 1080, 2137i, etc188.25.49.107 (talk) 12:02, 19 July 2011 (UTC)

AVCHD Vendor specific implementation "main-profile 4.0 vs high-profile 4.1"

Can anyone cite an authoritative source for either 'main-profile 4.0' or 'high-profile 4.1'? Neither one makes sense.

From wikipedia's H264 article:

Levels with maximum property values
Level Max macroblocks Max video bit rate (VCL) Examples for high resolution @
frame rate
(max stored frames)
per second per frame BP, XP, MP
(kbit/s)
HiP
(kbit/s)
Hi10P
(kbit/s)
Hi422P, Hi444PP
(kbit/s)
4 245,760 8,192 20,000 25,000 ... ... 1,280×720@68.3 (9)
1,920×1,080@30.1 (4)
2,048×1,024@30.0 (4)
4.1 245,760 8,192 50,000 62,500 ... ... 1,280×720@68.3 (9)
1,920×1,080@30.1 (4)
2,048×1,024@30.0 (4)
4.2 522,240 8,704 50,000 62,500 ... ... 1,920×1,080@64.0 (4)
2,048×1,080@60.0 (4)
  For MP@L4.0: maximum-bitrate = 20,000bps  (20Mbps)
  For HP@L4.0: maximum-bitrate = 25,000bps  (25Mbps)

Furthermore, I ran the raw camera bitstreams of several brands (Panasonic, Sony, Canon) through MediaInfo, an open-source mpeg reporting tool. There were no MainProfile (MP) bitstreams (I didn't try the earliest 2006 AVCHD models.) And there were no HP@L4.1 bitstreams. It's pretty clear the older camcorders had inferior compression quality (and probably used fewer H264 encoding features), but that is immaterial to the issue at hand...every video-sequence of every AVCHD/AVCHD-lite bitstream that I came across was reported by MediaInfo as "HP@L4.0"

Sony CX550v (1080i30) http://av.watch.impress.co.jp/docs/series/zooma/20100203_346539.html

Panasonic TM700 (1080i30) http://av.watch.impress.co.jp/docs/series/zooma/20100324_356414.html

Sony SR11 (1080i30) http://av.watch.impress.co.jp/docs/20080312/zooma349.htm

Panasonic SD9 (1080p24) http://www.watch.impress.co.jp/av/docs/20080305/zooma348.htm

(Rest of the raw bitstreams, Canon HF-S21, Panasonic, I pulled from user-uploads at vimeo)

...The logical conclusion is that the AVCHD specification mandates Level 4.0. Unless, of course, Panasonic/Sony planned a future extension beyond 25Mbps, in which case it would make sense to mandate L4.1, even though the current published spec limits bitrate to a much lower rate of 25Mbps. (It is odd, but not illegal application of the spec.)

I suppose the main-profile vs high-profile is a separate issue to be visited another day.

I tried MediaInfo myself, and all I could see was HP@L4.0. I tried files from the HG10, the HF100, the SD100, the TM300. 1080p50 and 1080p50 files from the TM700 shows HP@L4.2, as it is supposed to be. I haven't tried files from the HF-S family, maybe it uses L4.1, did you say you tried it too and it was L4.0? I put request for citation for L4.1 statement made for Canon cameras (some people get twitchy when I just fix unreliable info).
It seems that either BD uses L4.1, or a "more compatible" AVCHD should be L4.1. MultiAVCHD has a separate "Force Level 4.1" checkbox, which is supposed to provide better compatibility with BD players. Naturally, I unchecked this setting when I was mastering 1080p60 footage, which has higher level 4.2 Mikus (talk) 16:47, 4 May 2010 (UTC)
Can you explain why did you remove each and any reference to H.264 Profiles? I see no harm in mentioning here that 720p25/p30 and 1080p25/p30 require HP L4.0, and 1080p50/p60 require HP L4.2; this is not instantly evident from reading the H.264 article, in fact you must dive quite deeply to even get to the profiles table. --82.179.218.11 (talk) 10:43, 18 November 2010 (UTC)
I did that because people were posting controversial information about profiles and levels, in particular usage of level 4.1 in pro Panasonic camcorders, which supposedly made them better in picture quality compared to consumer models. I tested many native clips from different camcorders including Panasonic HMC150, HMC40 and Sony AX2000, NX5 and I did not find clips with level 4.1, all were 4.0. You may call it original research, but their info was no better. The official AVCHD spec does not say anything about profile and level. Hence I removed this information from the article. I believe that I left an explicit note about 1080-line 50p/60p modes of the new Panasonic cameras, which record at level 4.2. On the other hand, this level can be deducted from AVC/H.264 page, which is linked from AVCHD page. Not sure that profile/level info should be mentioned in this article at all. Mikus (talk) 23:55, 2 December 2010 (UTC)

I suggest removing hardware and software product lists

When AVCHD had started, there were few camcorder models and few software packages that accepted AVCHD. In five years many models came and went, and most NLEs currently support AVCHD. I am thinking of removing these lists, keeping only the most notable models. Mikus (talk) 00:36, 22 January 2011 (UTC)

Likewise, the cluttered listing of models (by manufacturer) should be entirely removed, or trimmed down to only current year-models. Wikipedia is not a manufacturer product archive, most of the listed models are not noteworthy in and of themselves, and mixing consumer camcorders, prosumer camcorders, digital cameras, and multifunction devices only serves to clutter the article with off-topic trivia. Here's an example: "In the consumer market, 60 Hz versions of the Panasonic HDC-SD9/HDC-HS9, Panasonic HDC-HS100/HDC-SD100 and Canon HF S21/HF S20/HF S200 models are capable of recording native 1080p24 video." Those (USA) models have been out of production for 3 years, they are no longer carried by Panasonic, and quite frankly, listing that alongside current-year models serves only to confuse the reader. It would be better to have a cursory remark "Support for 1080p24 recording is comparitively less common, generally only found in prosumer equipment, and hybrid digital cameras (such as the Panasonic GH-2.)" Trying to list every model which does 1 particular feature of the standard doesn't contribute to anyone's understanding. In other words, the article should focus on the format itself, not on "what has AVCHD feature XYZ." —Preceding unsigned comment added by 99.188.150.12 (talk) 21:08, 26 February 2011 (UTC)
Well, how do you deliver the idea that 2-3 years ago Panasonic offered consumer camcorders that recorded native 24p, but current models use pulldown instead? A year and a half ago the AG-HMC40 was released, which is based on the HS300/SD300 hardware but has bigger body and a bunch of professional functions? The "300" use pulldown, while the HMC40 offers native 24p. As this is a wiki article and not an essay, I cannot put here my own conspiracy theories but I want to at least give the readers cold data and timeline to draw their own conclusions from. I think about creating separate sections for 24p and 50p/60p.
Or maybe I will change the sections as follows:
  • interlaced recording
    • standard definition recording
    • 1080i
  • progressive recording
    • 720p
    • 1080p
And I will mention the above tidbits when discussing various framerates in either mode.Mikus (talk) 17:57, 28 February 2011 (UTC)
Removing the lists is a good idea. --Regression Tester (talk) 17:04, 27 February 2011 (UTC)

Trimming of irrelevant content

I think the article suffers from an attempt to cram too much product-level trivia into what ought to be an overview of the AVCHD recording format. For example, the media section has a list of 'pros/cons' for each media-type. In my opinion, this pro/con discussion sidetracks the article, as most of those issues aren't unique or tied to AVCHD, but rather generic arguments for media-storage in general. It would be much more concise, and pertinent, to omit the listed pros/cons, and simply summarize the officially supported media types (DVD disc, removable media like SD-card and Sony memstick.) Models with an internal storage (whether its flash-based or hard disk) generally function as a USB mass storage device (imprinted with the AVCHD file-system) when connected to a PC. That keeps the media discussion on topic, and relevant to the details of AVCHD.

The sections should be on topic and to the point. Not saying it is easy to organize the article like that, but I think it's a worthy goal.

The "compatibility-list" (players, in particular) feels out of place in this article. Information like that is timely (i.e. changing on a monthly basis), and belongs on a dedicated website, but not in a wikipedia article. The article could reference a help-site with this info, however. —Preceding unsigned comment added by 99.106.241.229 (talk) 05:18, 18 March 2011 (UTC)

"Related formats" subsection

iFrame and AVC-Intra? Could someone site an autoritative reference linking these two formats to AVCHD? Based on the text in the article, there is no relation whatsoever, other than the fact that all three use the H264 video codec.

Does that mean HDV is related to AVCHD, because after all, both store compressed A+V stream in an MPEG-2 transport stream? How about the millions of generic MPEG-4 video recorders that store movie files in Quicktime movie containers( H264 + PCM audio)? Well that has *TWO* items in comon with AVCHD, H264 and PCM-audio!

Perhaps JPEG is related to AVCHD too! After all, nearly all AVCHD camcorders take still-snapshots in JPEG format!

...since the adjective "related" is subject to side interpretation, this entire section should be removed. It implies that there is some kind of tie between the AVCHD and non-AVCHD formats, when really, there is no basis to make that remark. Unless there is some official statement from an authoritative source (such as the specification document) which proves otherwise. — Preceding unsigned comment added by 99.60.52.252 (talk) 15:13, 9 July 2011 (UTC)

AVCHD - Extensions to specification

Would it be relevant to the AVDHC entry if someone could add the updated specifications for AVDHC which were announced at the beginning of July 2011 and which now include AVCHD Progessive, AVCHD Progessive/3D and AVCHD 3D ?

More info at

http://www.avchd-info.org/

http://www.avchd-info.org/format/OverviewChart2.jpg

Manowight (talk) 17:48, 15 July 2011 (UTC)

Complete lack of xvYCC

Completely missing from the article is any reference to the xvYCC gamut that is part of the AVCHD specification. Aside from DCI, this appears to be the only standardized color space for video recording that is wider than the vanilla BT.601 and BT.709 gamut defintions. It could be a very intersting feature, bringing us closer to cinematographic color reproduction, at least outside the broadcast realm, however appears to be totally neglected by manufacturers (aside from using it for marketing reasons). I am not competent engough to write something on it, and my WWW searches so far were vastly futile, e.g. in respect to editors able to maintain the gamut, or displaying it from computers via HDMI adapters (HDMI being the only protocol so far that supports xvYCC output). Thyl Engelhardt213.70.217.172 (talk) 08:12, 28 August 2011 (UTC)

Also, which screen supports better than sRGB/709? — Preceding unsigned comment added by 192.102.250.181 (talk) 08:07, 24 October 2011 (UTC)

Interlaced Designed for Cathode Ray ??

The statement "Interlaced video had been originally designed for watching on a cathode-ray tube television set." is completely false, interlacing has nothing to do with cathode ray tubes. The idea had two reasons: 1.) film was 'flashing' at 48 Hz. This flashing had to be maintained within the bandwidth. 2.) Film was really bad at fast motion. If the camera 'paned' - especially in telephoto - the image was really jerky. Interlacing smoothers this jerkiness. Using the latest-n-greatest camera in 25p mode will be just as jerky on the latest-n-greatest screen as film was. (This is what many believes to be a 'film-look'.) The 50i mode is smoother at the same bandwidth as 25p and the 50p will be best - at twice the bandwidth of 50i/25p. — Preceding unsigned comment added by 192.102.250.181 (talk) 08:35, 24 October 2011 (UTC)

Interlaced video was expressly designed for watching on a cathode ray tube, given that in 1936 there was no other way of watching it (ignoring Baird's televisor which was long gone by this time). DieSwartzPunkt (talk) 17:04, 28 November 2011 (UTC)

Capacity of DVDs

The optical disc technology may allow better pit packing, smaller pit sizes or more layers, but these will not be the same DVDs we use in consumer DVD players. These players can understand double-layer discs at best. Other developments are called differently. After all, what is Blu-ray Disc if not a DVD disc with higher pit packing and different laser wavelength? Mikus (talk) 19:04, 1 December 2011 (UTC)

I feel pretty certain that if a 3 (or 4, or 5 ...) layer variant of the DVD was produced based on the 650 nm laser wavelength, it would still be known as a 'DVD' especially as existing players could easily play them (with a suitable firmware upgrade). You are, of course, entirely correct when you observe that a blu-ray disc is nothing more complex than the DVD technology (actually DVD+) using a shorter wavelength laser (405 nm). However, since existing DVD players could never play them (even with a firmware upgrade) that would pose a marketing problem over the DVD logo identifying comatability. Thus it had to be called something else. You may recall that Toshiba announced (but didn't deliver before they threw in the towel) a 3 layer variant of the HD DVD format, which they were still going to call 'HD DVD'. I grant that the DVD is unlikely to be developed much further, but that does not mean that the limit of its development has been reached for reasons that we have both provided. DieSwartzPunkt (talk) 12:50, 2 December 2011 (UTC)
"it would still be known as a 'DVD' especially as existing players could easily play them (with a suitable firmware upgrade)." - I assume this is purely speculation on your side. I personally don't know whether ALL existing DVD players can be easily upgraded to more than two layers. In any case, as current DVD technology (one that bears "DVD" name as opposed to all other names like HD DVD or Blu-ray) is winding down, I don't see any future developments beyond double-layer DVDs. Even with double-layer, some earlier players have difficulty playing them at all, while many other players experience delay up to 5 seconds during layer change. Thus, I stand my ground: DVD technology (again, in consumer marketing terms) has come to its end. If any optical disc technology will continue on, it will be based on Blu-ray, which is not DVD. Mikus (talk) 16:42, 2 December 2011 (UTC)
It should only require a firmware change as the optical assembly should be perfectly capable of focussing over the range required - after all the data track on a CD is in a different place to that on a DVD and every DVD player that I know of can read CDs (and most actually use the DVD laser for pre mastered and CD-RW discs). The firmware just needs to know about the new book codes; the extra layers and how to play them. The players that have difficulty playing dual layer discs are generally suffering from a reduced laser output (dual layer discs have a lower reflectivity). The laser output unfortunately diminishes with age. Early generation CD players had a photo diode as part of the optical block so that the laser drive could be increased as it aged. This was soon omitted once the manufacturers figured out that laser failure wasn't generally their problem as it most often happens after the warranty has lapsed. No DVD drive mechanism (video or data) that I am aware of has a photo diode - hence the relatively short life. I never expect a computer drive to last much longer than 2-3 years and video DVD players don't last that much longer. Even my first blu-ray player started mis-reading blu-ray discs after just 18 months.
All players experience a delay when changing from one layer to another (I am unaware of any that don't). This is because the optical assembly has to locate the start of the track; focus on it and then the processor has to synchronise to the data stream (especially if playing Dolby or DTS sound). The job is made easier on video DVDs because they are (generally) authored such that track 1 starts in the same physical place that track 0 finishes so there should be no need to find the start of the track.
I actually agreed with you that there is unlikely to be any further development of the DVD format but, as I said, it most certainly hasn't hit any limit on how it could be developed. As highly unlikely as you or I believe it to be doesn't make it impossible - just highly unlikely. A statement in an encyclopeadic article claiming that it has reached a limit would be untrue (but then this is wikipedia which is not noted for its accuracy!). DieSwartzPunkt (talk) 17:57, 2 December 2011 (UTC)
The point was that it is extremely unlikely that DVD technology (in particular used for DVD-Video) will continue to evolve. Blu-Ray has become the next step in optical media development, while other media types like built-in HDDs and memory cards continue to grow in capacity, fully retaining physical size and electric interface. Try phrasing this idea yourself. Mikus (talk) 17:10, 3 December 2011 (UTC)
That wouldn't be too difficult, but the other thing that occurs to me is that it isn't really a disadvantage of the format. DieSwartzPunkt (talk) 18:37, 3 December 2011 (UTC)
1.4GB per one single-layer 8-cm disc is surely a disadvantage. No wonder that currently no company offers camcorders that record onto optical media. Even Blu-ray discs are not viable now when 32GB memory cards are ubiquitous. Mikus (talk) 05:32, 4 December 2011 (UTC)

────────────────────────────────────────────────────────────────────────────────────────────────────It occured to me last night that the limitation is only because our thinking is confined to DVD. If we think "optical disc", the limitations disappear because the DVD evolved into the blu-ray, and there is still no limit in sight. Now we have ultra violet lasers available another increase in capacity is available. I agree that 8 cm blu-ray (or any successor) camcorder is unlikely to appear because, as you rightly note, hard disc and flash memory technology has trumped it as far as a convenient camcorder storage system is concerned. Thus there is no limit - yet. I have added a suitable point to the article that encompasses much that we have discusssed as you suggested. See what you think and improve accordingly. DieSwartzPunkt (talk) 12:28, 4 December 2011 (UTC)


So having stated above that, "... currently no company offers camcorders that record onto optical media", did you revert the point in the article? Oh yes, I'm forgetting, it's your article, and you don't want anyone else editing your text. DieSwartzPunkt (talk) 09:21, 31 January 2012 (UTC)

This article is owned and arbitrated by User:Mikus

This article is apparently owned by User:Mikus who has self appointed himself as arbiter of what may appear in it and whether a particular citation is acceptable for the point being made.

Evidence is contained in his reverting an edit because he didn't like it, with the edit summary, "I like the older version better ...".

But the real clincher is this edit summary, "I suggest you stop ruining others' articles and start your own. Everyone who works with AVCHD knows what AVCHD disc is" [My emphasis]. This clearly shows that he regards articles as 'owned'.

This is not permitted under Wikipedia policy (See WP:OWNERSHIP). And certainly appointing your self as arbiter is forbidden. Articles are a collabarative effort, and all editors are equally entitled to contribute to an article. In fact the page on Ownership (and I know you haven't bothered to read it because we have had this discussion before) says:

<QUOTE>

All Wikipedia content[1] is open to being edited collaboratively. No one, no matter how skilled, and regardless of their standing in the community, has the right to act as if they are the owner of a particular article. </QUOTE>

That last edit summary also shows another point. That Mikus believes that the term 'AVCHD disc' is in common usage purely because, "Everyone who works with AVCHD knows what AVCHD disc is". Not even close to a valid reason, and there is also plenty of evidence that it is not the case. Indeed, an encyclopedic article on AVCHD is not written for those people who know what an AVCHD disc is - it is written for those who don't and they require evidence that it is a legitimate and universally accepted and used description (i.e. a citation establishing positively that that is the case).

There is no shortage of evidence that is not in common usage. In fact his own restored citation is, in reality, evidence that it is not so. His own citation doesn't define AVCHD disc at all, but merely states, "In this manual, the DVD disc recorded with high definition image quality (HD) is called AVCHD disc.". Thus the author of this text obviously dos not regard the term 'AVCHD disc' as being in general usage, but has to explain its use within the confines of that manual.

Taking 3 other cases at random (purely because I can easily lay hands on the documentation). I have a Philips Blu-Ray disc player. The machine plays DVD discs with AVCHD material without problem. The user manual does not contain the term 'AVCHD disc' anywhere in the text. So Philips don't use the term. I tried to find a link to an online version but failed.

I have a Panasonic camcorder that is able to record DVD discs with the AVCHD material (when it is connected to a suitable DVD burner). The user manual does not contain the term 'AVCHD disc' anywhere throughout the text. So Panasonic don't use the term. I have a link to this one [[1]], so you can see for yourself. Indeed no Panasonic documentation that I can find, even though they were one of the instigators of the AVCHD format (particularly on DVD), uses the term.

The PC based DVD (and Blu-ray) video playing software, PowerDVD plays DVD discs containing AVCHD material. Once again, the user documentation does not mention the term 'AVCHD disc' anywhere. So Cyberlink don't use the term.

I could probabbly go on, but I regard four instances of evidence that is not even in common usage, let alone universal, as adequate proof that the them 'AVCHD disc' is not in as general use as Mikus believes, but then he is the arbiter of what is and is not valid in this artcle - at least in his eyes.

AFAICT, the term only seems to show up in Sony documentation and may even be a trade mark (particularly as Sony have a logo for the format). DieSwartzPunkt (talk) 08:52, 31 January 2012 (UTC)

Further evidence

Mikus posted this on my talk page, "Yes, I did spend considerable time licking the article out and I want it to look nice, to be useful to general public and to be readable.". Yet further evidence of ownership. DieSwartzPunkt (talk) 15:14, 1 February 2012 (UTC)

Playback in quicktime

I've just removed the following bit: ", additional (free) software is required.[2]" Following that reference leads to a recently-updated article clarifying that quicktime in fact does not play avchd and it mentions no add-ons. Previously, a comment on the article had claimed that it did but the article now mentions the comment but suggests that there's a confusion. 86.148.226.218 (talk) 23:59, 6 May 2012 (UTC)

Re: removed purported "Con" [this date]

This "con" is not really related to either device or technology. A lot of valuable things are of small form factor, and therefore easily misplaced if mishandled. However, if you can safeguard a diamond, you can safeguard a microSD card. Priorities. After all, it's not like most people are still using VHS as primary recording media; most users today are familiar with, indeed expect, minaturized memory storage. Submitted with all due respect -- James — Preceding unsigned comment added by 108.46.171.97 (talk) 19:46, 24 February 2013 (UTC)

Suggesting to remove the model list

Seven years into the standard there are way too many cameras shooting in AVCHD. I suggest removing the model list altogether. Same for Blu-ray player list, it is not comprehensive and unofficial, based on someone's experience. Mikus (talk) 16:52, 6 May 2013 (UTC)

AVCHD vs. other formats

Is there a place I can go to find out the advantages of this format vs. other formats? For example, is this format more compressed than others? Why would I choose this format over others? What format is the "best" for various jobs? N0w8st8s (talk) 10:23, 21 October 2013 (UTC)n0w8st8s

Release of first SONY AVCHD camcorder

Panasonic's literature gives the release date of HDC-SD1 and HDC-DX1 as autumn 2006. The SONY offering cannot possibly be as late as 2010, but I cannot find a definitive date. Any offers? 86.150.65.49 (talk) 19:53, 19 November 2013 (UTC)

Not quite correct. The AVCHD format was announced in 2006, but the only evidence that I can find suggests that the first two Panasonic cameras to use the format were released in the spring of 2007. This is based on the oldest review that I can find (August 2007), which happliy stated that the cameras had been released a few months earlier. If anyone is wondering why two cameras were released, it is because one recorded to mini DVD discs, the other to SDHC FLASH memory cards. The earliest review that I can find for a Sony AVCHD camcorder (model HDR-HC7 - a hard disc based machine) is also dated 2007 (so that knocks the 2010 date into a cocked hat) and it also suggests a spring launch. Since the format was a joint venture, it is not unreasonable to expect first models at roughly the same time. I have ammended the article on both earliest models. DieSwartzPunkt (talk) 17:27, 20 November 2013 (UTC)