FFmpeg

112576 Commits

37 Branches

400 Tags

492 MiB

Tag: Branch: Tree: 61df86efdd

Commit Graph

Author	SHA1	Message	Date
James Almer	8564b4ab05	avfilter/ccfifo: constify some parameters Signed-off-by: James Almer <jamrial@gmail.com>	2 years ago
James Almer	7f890b2fbb	avfilter/ccfifo: remove unnecessary context allocations This is not public API, no it has no need for an alloc() and free() functions. The struct can reside on stack. Signed-off-by: James Almer <jamrial@gmail.com>	2 years ago
Devin Heitmueller	2b0e794ffc	avfilter/ccfifo: Properly handle CEA-708 captions through framerate conversion When transcoding video that contains 708 closed captions, the caption data is tied to the frames as side data. Simply dropping or adding frames to change the framerate will result in loss of data, so the caption data needs to be preserved and reformatted. For example, without this patch converting 720p59 to 1080i59 would result in loss of 50% of the caption bytes, resulting in garbled 608 captions and 708 probably wouldn't render at all. Further, the frames that are there will have an illegal cc_count for the target framerate, so some decoders may ignore the packets entirely. Extract the 608 and 708 tuples and insert them onto queues. Then after dropping/adding frames, re-write the tuples back into the resulting frames at the appropriate rate given the target framerate. This includes both having the correct cc_count as well as clocking out the 608 pairs at the appropriate rate. Thanks to Lance Wang <lance.lmwang@gmail.com>, Anton Khirnov <anton@khirnov.net>, and Michael Niedermayer <michael@niedermayer.cc> for providing review/feedback. Signed-off-by: Devin Heitmueller <dheitmueller@ltnglobal.com> Signed-off-by: Limin Wang <lance.lmwang@gmail.com>	2 years ago

Author

SHA1

Message

Date

James Almer

8564b4ab05

avfilter/ccfifo: constify some parameters

Signed-off-by: James Almer <jamrial@gmail.com>

2 years ago

James Almer

7f890b2fbb

avfilter/ccfifo: remove unnecessary context allocations

This is not public API, no it has no need for an alloc() and free()
functions. The struct can reside on stack.

Signed-off-by: James Almer <jamrial@gmail.com>

2 years ago

Devin Heitmueller

2b0e794ffc

avfilter/ccfifo: Properly handle CEA-708 captions through framerate conversion

When transcoding video that contains 708 closed captions, the
caption data is tied to the frames as side data.  Simply dropping
or adding frames to change the framerate will result in loss of
data, so the caption data needs to be preserved and reformatted.

For example, without this patch converting 720p59 to 1080i59
would result in loss of 50% of the caption bytes, resulting in
garbled 608 captions and 708 probably wouldn't render at all.
Further, the frames that are there will have an illegal
cc_count for the target framerate, so some decoders may ignore
the packets entirely.

Extract the 608 and 708 tuples and insert them onto queues.  Then
after dropping/adding frames, re-write the tuples back into the
resulting frames at the appropriate rate given the target
framerate.  This includes both having the correct cc_count as
well as clocking out the 608 pairs at the appropriate rate.

Thanks to Lance Wang <lance.lmwang@gmail.com>, Anton
Khirnov <anton@khirnov.net>, and Michael Niedermayer <michael@niedermayer.cc>
for providing review/feedback.

Signed-off-by: Devin Heitmueller <dheitmueller@ltnglobal.com>
Signed-off-by: Limin Wang <lance.lmwang@gmail.com>

2 years ago

3 Commits (61df86efdd5e5437345e080e646476a12c71b855)