问题
SO...
I am trying to take a H264 Annex B byte stream video and encode it into MPEG-TS in pure Java. My goals is to create a minimal MPEG-TS, Single Program, valid stream and to not include any timing information information (PCR, PTS, DTS).
I am currently at the point where my generated file can be passed to ffmpeg (ffmpeg -i myVideo.ts) and ffmpeg reports...
[NULL @ 0x7f8103022600] start time is not set in estimate_timings_from_pts
Input #0, mpegts, from 'video.ts':
Duration: N/A, bitrate: N/A
Program 1
Stream #0:0[0x100]: Video: h264 (Main) ([27][0][0][0] / 0x001B), yuv420p(tv, bt709), 1280x720 [SAR 1:1 DAR 16:9], 29.97 fps, 29.97 tbr, 90k tbn, 59.94 tbc
...it seems like this warning for start time is not a big deal... and ffmpeg is unable to determine how long the video is. If I create another mpeg-ts file from my video file (ffmpeg -i myVideo.ts -vcodec copy validVideo.ts) and run ffmpeg -i validVideo.ts I get...
Input #0, mpegts, from 'video2.ts':
Duration: 00:00:11.61, start: 1.400000, bitrate: 3325 kb/s
Program 1
Metadata:
service_name : Service01
service_provider: FFmpeg
Stream #0:0[0x100]: Video: h264 (Main) ([27][0][0][0] / 0x001B), yuv420p(tv, bt709), 1280x720 [SAR 1:1 DAR 16:9], 29.97 fps, 29.97 tbr, 90k tbn, 59.94 tbc
...so you can see the timing information and bitrate is there and so is the metadata.
My H264 video is comprised of only I and P Frames (with the SPS and PPS preceding the I Frame of course) and the way that I am creating my MPEG-TS stream is...
- Write a single PAT at the beginning of the file
- Write a single PMT at the beginning of the file
- Create TS and PES packets from SPS, PPS and I Frame (AUD NALs too, if this is required?)
- Create TS and PES packets from P Frame (again, AUD NALs too, if required)
- For the last payload of either an I Frame or P Frame, add filler bytes to an adaptation field to make sure it fits into a full TS packet
- Repeat 3-5 for the entire file
...my PAT looks like this...
4740 0010 0000 b00d 0001 c100 0000 01f0
002a b104 b2ff ffff ffff ffff ffff ffff
ffff ffff ffff ffff ffff ffff ffff ffff
ffff ffff ffff ffff ffff ffff ffff ffff
ffff ffff ffff ffff ffff ffff ffff ffff
ffff ffff ffff ffff ffff ffff ffff ffff
ffff ffff ffff ffff ffff ffff ffff ffff
ffff ffff ffff ffff ffff ffff ffff ffff
ffff ffff ffff ffff ffff ffff ffff ffff
ffff ffff ffff ffff ffff ffff ffff ffff
ffff ffff ffff ffff ffff ffff ffff ffff
ffff ffff ffff ffff ffff ffff
...and my PMT looks like this...
4750 0010
0002 b012 0001 c100 00ff fff0 001b e100
f000 c15b 41e0 ffff ffff ffff ffff ffff
ffff ffff ffff ffff ffff ffff ffff ffff
ffff ffff ffff ffff ffff ffff ffff ffff
ffff ffff ffff ffff ffff ffff ffff ffff
ffff ffff ffff ffff ffff ffff ffff ffff
ffff ffff ffff ffff ffff ffff ffff ffff
ffff ffff ffff ffff ffff ffff ffff ffff
ffff ffff ffff ffff ffff ffff ffff ffff
ffff ffff ffff ffff ffff ffff ffff ffff
ffff ffff ffff ffff ffff ffff ffff ffff
ffff ffff ffff ffff
...notice after the c100 00, the "ff ff", f0... says that we are not using a PCR... Also notice that I have updated my CRC to reflect this change to the PMT. My first I Frame packet looks like...
4741 0010 0000 01e0
0000 8000 0000 0000 0109 f000 0000 0127
4d40 288d 8d60 2802 dd80 b501 0101 4000
00fa 4000 3a98 3a18 00b7 2000 3380 2ef2
e343 0016 e400 0670 05de 5c16 345d c000
0000 0128 ee3c 8000 0000 0165 8880 0020
0000 4fe5 63b5 4e90 b11c 9f8f f891 10f3
13b1 666b 9fc6 03e9 e321 36bf 1788 347b
eb23 fc89 5772 6e2e 1714 96df ed16 9b30
252d ceb7 07e9 a0c7 c6e7 9515 be87 2df1
81f3 b9d2 ba5f 243e 2d5c cba2 8ca5 b798
6bec 8c43 0b5d bbda bc5b 6e7c e15c 84e8
2f13 be84
...you'll notice after the 01e0 0000, 8000 00 is the PES header extension where I specify no PTS / DTS and the remaining length is zero. My first P Frame packet looks like...
4741 001d
0000 01e0 0000 8000 0000 0000 0109 f000
0000 0141 9a00 0200 0593 ff45 a7ae 1acd
f2d7 f9ec 557f cdb6 ba38 60d6 a626 5edb
4bb9 9783 89e2 d7e1 102e 4625 2fbf ce16
f952 d8c9 f027 e55a 6b2a 81c3 48d4 6a45
050a f355 fbec db01 6562 6405 04aa e011
50ec 0b45 45e5 0df7 2fed a3f8 ac13 2e69
6739 6d81 f13d 2455 e6ca 1c6b dc96 65d5
3bad f250 7dab 42e4 7ba9 f564 ee61 29fb
1b2c 974c 6924 1a1f 99ef 063c b99a c507
8c22 b0f8 b14c 3e4d 01d0 6120 4e19 8725
2fda 6550 f907 3f87
...and whenever an I Frame or P Frame is ending, I have a TS packet with an adaptation field like...
4701 003c b000 ffff ffff ffff ffff ffff
ffff ffff ffff ffff ffff ffff ffff ffff
ffff ffff ffff ffff ffff ffff ffff ffff
ffff ffff ffff ffff ffff ffff ffff ffff
ffff ffff ffff ffff ffff ffff ffff ffff
ffff ffff ffff ffff ffff ffff ffff ffff
ffff ffff ffff ffff ffff ffff ffff ffff
ffff ffff ffff ffff ffff ffff ffff ffff
ffff ffff ffff ffff ffff ffff ffff ffff
ffff ffff ffff ffff ffff ffff ffff ffff
ffff ffff ffff ffff ffff ffff ffff ffff
ffff ffff ffff ffff ffff ffff
...where the first b0 bytes are the adaptation field stuffing bytes and the remaining ones are the final bytes of the I or P Frame. So as you can tell I can use ffmpeg and pass it my file to create a valid movie in any format. However, I need the file I create to be in the proper format and I cannot quite figure out what the last piece I am missing is. Any ideas?
回答1:
You have conflicting requirements. "valid stream" and "not include any timing information" are incompatible. It is a requirement of TS to have a PCR at least every 100 milliseconds. And while player specific, most players will not 'present' a frame without a 'presentation time stamp'. You my be able to derive the timestamp from the VUI data, but it must exist in the container.
来源：https://stackoverflow.com/questions/24564680/manual-encoding-into-mpeg-ts