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In [[MPEG]] video |
In [[MPEG]] [[video encoding]], a '''group of pictures''', or '''GOP''', specifies the order in which [[intra-frame]]s and [[inter-frame]]s are arranged. |
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The GOP is a group of successive pictures within a MPEG-coded film and/or video stream. Each MPEG-coded film and/or video stream consists of successive GOPs. From the MPEG pictures contained in it the visible frames are generated. |
The GOP is a group of successive pictures within a MPEG-coded film and/or video stream. Each MPEG-coded film and/or video stream consists of successive GOPs. From the MPEG pictures contained in it the visible frames are generated. |
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A GOP can contain the following picture types: |
A GOP can contain the following picture types: |
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*I-picture and/or I-Frame (English intra coded picture) reference picture, corresponds to a fixed image and is independent of other picture types. Each GOP begins with this type of picture. |
*[[I-picture]] and/or [[I-Frame]] (English intra coded picture) reference picture, corresponds to a fixed image and is independent of other picture types. Each GOP begins with this type of picture. |
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*P-picture and/or P-Frame (English predictive coded picture) contains difference information from the preceding i or P-Frame. |
*[[P-picture]] and/or [[P-Frame]] (English predictive coded picture) contains difference information from the preceding i or P-Frame. |
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*B-picture and/or B-Frame (English bidirectionally predictive coded pictures) contains difference information from the preceding and/or following i or P-Frame. |
*[[B-picture]] and/or [[B-Frame]] (English bidirectionally predictive coded pictures) contains difference information from the preceding and/or following i or P-Frame. |
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*D-picture and/or D-Frame (English DC direct coded picture) serves the fast advance. |
*[[D-picture]] and/or [[D-Frame]] (English DC direct coded picture) serves the fast advance. |
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A GOP always begins with an I-Frame. Afterwards several P-Frames follow, in each case with some frames distance. In the remaining gaps are B-Frames. With the next I-Frame a new GOP begins. |
A GOP always begins with an I-Frame. Afterwards several P-Frames follow, in each case with some frames distance. In the remaining gaps are B-Frames. With the next I-Frame a new GOP begins. |
Revision as of 12:48, 13 January 2007
In MPEG video encoding, a group of pictures, or GOP, specifies the order in which intra-frames and inter-frames are arranged.
The GOP is a group of successive pictures within a MPEG-coded film and/or video stream. Each MPEG-coded film and/or video stream consists of successive GOPs. From the MPEG pictures contained in it the visible frames are generated.
A GOP can contain the following picture types:
- I-picture and/or I-Frame (English intra coded picture) reference picture, corresponds to a fixed image and is independent of other picture types. Each GOP begins with this type of picture.
- P-picture and/or P-Frame (English predictive coded picture) contains difference information from the preceding i or P-Frame.
- B-picture and/or B-Frame (English bidirectionally predictive coded pictures) contains difference information from the preceding and/or following i or P-Frame.
- D-picture and/or D-Frame (English DC direct coded picture) serves the fast advance.
A GOP always begins with an I-Frame. Afterwards several P-Frames follow, in each case with some frames distance. In the remaining gaps are B-Frames. With the next I-Frame a new GOP begins.