How to add MPEG-TS demux and mpeg2video decoder

Question

How to add MPEG-TS demux and mpeg2video decoder

Luke-HSKim opened this issue a year ago · comments

I added followings to /configs/default/ffmpeg-config.txt to add MPEG-TS demux and mpeg2video decoder, but it was not successful.

--enable-demuxer=mpegts
--enable-decoder=mp1
--enable-decoder=mp2
--enable-decoder=mp3
--enable-decoder=mp3adu
--enable-decoder=mp3on4
--enable-decoder=mpeg1video
--enable-decoder=mpeg2video

How can i make MPEG-TS stream with MPEG2 Video?

Yahweasel · Answer 1 · Wed May 10 2023 05:18:02 GMT+0800 (China Standard Time)

It's pretty difficult to guess from this. I've never attempted MPEG-2 per se, though I have done H.263+, which is largely the same, and it works fine. Unfortunately, libav has some stunningly useless error messages, such as the one you're seeing...

My recommended next step would be to check whether the codec it's detecting is actually what it should be, by using avcodec_get_name on the codec ID in the stream.

Luke-HSKim · Answer 2 · Wed May 10 2023 05:54:48 GMT+0800 (China Standard Time)

This stream is from DVB-C network.

Input #0, mpegts, from 'D:\Crenova\sources\Tizen3\TiviconConnectTizenWebappPC\libav\capture_das_erste_131s_mpeg2.ts':
Duration: 00:02:11.44, start: 3980.301189, bitrate: 6822 kb/s
Stream #0:0[0x54]: Data: bin_data ([6][0][0][0] / 0x0006)
Stream #0:1[0x65]: Video: mpeg2video (Main) ([2][0][0][0] / 0x0002), yuv420p(tv, top first), 720x576 [SAR 64:45 DAR
16:9], 25 fps, 25 tbr, 90k tbn, 50 tbc
Stream #0:20x66: Audio: mp2 ([3][0][0][0] / 0x0003), 48000 Hz, stereo, fltp, 256 kb/s
Stream #0:30x67: Audio: mp2 ([3][0][0][0] / 0x0003), 48000 Hz, stereo, fltp, 192 kb/s (visual impaired) (desc
riptions)
Stream #0:40x68: Subtitle: dvb_teletext ([6][0][0][0] / 0x0006)
Stream #0:50x69: Subtitle: dvb_subtitle ([6][0][0][0] / 0x0006) (hearing impaired)
Stream #0:60x6a: Audio: ac3 ([6][0][0][0] / 0x0006), 48000 Hz, stereo, fltp, 448 kb/s
Stream #0:7[0x498]: Unknown: none ([12][0][0][0] / 0x000C)
Stream #0:8[0x816]: Unknown: none ([5][0][0][0] / 0x0005)
Stream #0:9[0x87b]: Unknown: none ([11][0][0][0] / 0x000B)

When I tried after adding "--enable-demuxer=mpegts", i saw "unsupported codec" or something like this. And I added the rests.

anything I missed except adding to ffmpeg-config.txt?

Yahweasel · Answer 3 · Wed May 10 2023 05:59:11 GMT+0800 (China Standard Time)

The question is, what does libav.js say about the codec, not what does ffmpeg say about the codec. I'm trying to narrow down where something's getting lost.

One thing is that you probably don't want to use default as a starting point. You should use one of the configurations that already supports video. They enable swscale, and libav can be pretty dopey with video if you don't have swscale, since that's how it does all pixel format conversions. That being said, it should at least be able to decode, so I don't really know...

Luke-HSKim · Answer 4 · Wed May 10 2023 18:23:02 GMT+0800 (China Standard Time)

Thank you for your kind explain!

Followings are all logs until i see alert popup. You can find codec name from libav.js in the middle.

libav-3.11.5.1.2-default.simd.js:708 Readahead input:0 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:32768 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:65536 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:98304 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:131072 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:163840 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:196608 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:229376 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:262144 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:294912 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:327680 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:360448 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:393216 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:425984 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:458752 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:491520 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:524288 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:557056 (32768)
demo.html:104 Stream 0: bin_data
demo.html:104 Stream 1: mpeg2video
demo.html:104 Stream 2: mp3
demo.html:104 Stream 3: mp3
demo.html:104 Stream 4: dvb_teletext
demo.html:104 Stream 5: dvb_subtitle
demo.html:104 Stream 6: ac3
demo.html:104 Stream 7: none
demo.html:104 Stream 8: none
demo.html:104 Stream 9: none
libav-3.11.5.1.2-default.simd.js:708 Readahead input:0 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:32768 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:65536 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:98304 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:131072 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:163840 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:196608 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:229376 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:262144 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:294912 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:327680 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:360448 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:393216 (32768)
libav-3.11.5.1.2-default.simd.js:708 [mpegts @ 0x287100] Packet corrupt (stream = 1, dts = 358295526).
put_char @ libav-3.11.5.1.2-default.simd.js:708
write @ libav-3.11.5.1.2-default.simd.js:708
write @ libav-3.11.5.1.2-default.simd.js:708
doWritev @ libav-3.11.5.1.2-default.simd.js:708
_fd_write @ libav-3.11.5.1.2-default.simd.js:708
$func1842 @ libav-3.11.5.1.2-default.simd.wasm:0x1f4332
$func1033 @ libav-3.11.5.1.2-default.simd.wasm:0x10acb2
$func1037 @ libav-3.11.5.1.2-default.simd.wasm:0x10af68
$func593 @ libav-3.11.5.1.2-default.simd.wasm:0x789d3
$func2041 @ libav-3.11.5.1.2-default.simd.wasm:0x21e0cf
$func30 @ libav-3.11.5.1.2-default.simd.wasm:0x1ff4
$func1106 @ libav-3.11.5.1.2-default.simd.wasm:0x1279ff
$func743 @ libav-3.11.5.1.2-default.simd.wasm:0x9e486
$Bd @ libav-3.11.5.1.2-default.simd.wasm:0x9f93f
ret. @ libav-3.11.5.1.2-default.simd.js:708
doRewind @ libav-3.11.5.1.2-default.simd.js:708
(anonymous) @ libav-3.11.5.1.2-default.simd.js:708
Promise.then (async)
(anonymous) @ libav-3.11.5.1.2-default.simd.js:708
handleSleep @ libav-3.11.5.1.2-default.simd.js:708
handleAsync @ libav-3.11.5.1.2-default.simd.js:708
libavjs_wait_reader @ libav-3.11.5.1.2-default.simd.js:708
$func1586 @ libav-3.11.5.1.2-default.simd.wasm:0x1a9163
$func2212 @ libav-3.11.5.1.2-default.simd.wasm:0x23651d
$func88 @ libav-3.11.5.1.2-default.simd.wasm:0xa23d
$func73 @ libav-3.11.5.1.2-default.simd.wasm:0x7289
$func1208 @ libav-3.11.5.1.2-default.simd.wasm:0x136ffc
$func448 @ libav-3.11.5.1.2-default.simd.wasm:0x51c83
$func931 @ libav-3.11.5.1.2-default.simd.wasm:0xe41eb
$func1650 @ libav-3.11.5.1.2-default.simd.wasm:0x1b5895
$func1106 @ libav-3.11.5.1.2-default.simd.wasm:0x1276f2
$func743 @ libav-3.11.5.1.2-default.simd.wasm:0x9e486
$Bd @ libav-3.11.5.1.2-default.simd.wasm:0x9f93f
ret. @ libav-3.11.5.1.2-default.simd.js:708
ccall @ libav-3.11.5.1.2-default.simd.js:708
(anonymous) @ libav-3.11.5.1.2-default.simd.js:708
(anonymous) @ libav-3.11.5.1.2-default.simd.js:708
Promise.then (async)
step @ libav-3.11.5.1.2-default.simd.js:708
Promise.then (async)
(anonymous) @ libav-3.11.5.1.2-default.simd.js:708
Promise.then (async)
step @ libav-3.11.5.1.2-default.simd.js:708
Promise.then (async)
(anonymous) @ libav-3.11.5.1.2-default.simd.js:708
Promise.then (async)
step @ libav-3.11.5.1.2-default.simd.js:708
Promise.then (async)
(anonymous) @ libav-3.11.5.1.2-default.simd.js:708
Promise.then (async)
step @ libav-3.11.5.1.2-default.simd.js:708
Promise.then (async)
(anonymous) @ libav-3.11.5.1.2-default.simd.js:708
Promise.then (async)
step @ libav-3.11.5.1.2-default.simd.js:708
Promise.then (async)
(anonymous) @ libav-3.11.5.1.2-default.simd.js:708
Promise.then (async)
step @ libav-3.11.5.1.2-default.simd.js:708
Promise.then (async)
(anonymous) @ libav-3.11.5.1.2-default.simd.js:708
Promise.then (async)
step @ libav-3.11.5.1.2-default.simd.js:708
Promise.then (async)
(anonymous) @ libav-3.11.5.1.2-default.simd.js:708
Promise.then (async)
step @ libav-3.11.5.1.2-default.simd.js:708
Promise.then (async)
(anonymous) @ libav-3.11.5.1.2-default.simd.js:708
Promise.then (async)
step @ libav-3.11.5.1.2-default.simd.js:708
Promise.then (async)
(anonymous) @ libav-3.11.5.1.2-default.simd.js:708
Promise.then (async)
step @ libav-3.11.5.1.2-default.simd.js:708
Promise.then (async)
(anonymous) @ libav-3.11.5.1.2-default.simd.js:708
Promise.then (async)
step @ libav-3.11.5.1.2-default.simd.js:708
Promise.then (async)
(anonymous) @ libav-3.11.5.1.2-default.simd.js:708
Promise.then (async)
step @ libav-3.11.5.1.2-default.simd.js:708
Promise.then (async)
(anonymous) @ libav-3.11.5.1.2-default.simd.js:708
Promise.then (async)
step @ libav-3.11.5.1.2-default.simd.js:708
Promise.then (async)
(anonymous) @ libav-3.11.5.1.2-default.simd.js:708
Promise.then (async)
step @ libav-3.11.5.1.2-default.simd.js:708
Promise.then (async)
(anonymous) @ libav-3.11.5.1.2-default.simd.js:708
Promise.then (async)
step @ libav-3.11.5.1.2-default.simd.js:708
Promise.then (async)
(anonymous) @ libav-3.11.5.1.2-default.simd.js:708
Promise.then (async)
step @ libav-3.11.5.1.2-default.simd.js:708
libav-3.11.5.1.2-default.simd.js:708 Readahead input:425984 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:458752 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:491520 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:524288 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:557056 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:589824 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:622592 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:655360 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:688128 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:720896 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:753664 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:786432 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:819200 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:851968 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:884736 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:917504 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:950272 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:983040 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:1015808 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:1048576 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:1081344 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:1114112 (32768)
libav-3.11.5.1.2-default.simd.js:708 Readahead input:1146880 (32768)
libav-3.11.5.1.2-default.simd.js:708 [mpeg2video @ 0x2d3380] Invalid frame dimensions 0x0.
p

Yahweasel · Answer 5 · Wed May 10 2023 21:52:05 GMT+0800 (China Standard Time)

« libav-3.11.5.1.2-default.simd.js:708 [mpegts @ 0x287100] Packet corrupt (stream = 1, dts = 358295526).»

This is the most suspicious line. Either this is not a valid mpegts stream (mpegps stream?), or something is missing in the demuxing code. What does desktop ffprobe report the file as? Maybe this just isn't the right/most general demuxer.

Luke-HSKim · Answer 6 · Wed May 10 2023 22:04:42 GMT+0800 (China Standard Time)

ffprobe.exe capture_das_erste_131s_mpeg2.ts
ffprobe version N-91672-gd0b48a9604 Copyright (c) 2007-2018 the FFmpeg developers
built with gcc 8.2.1 (GCC) 20180813
configuration: --enable-gpl --enable-version3 --enable-sdl2 --enable-fontconfig --enable-gnutls --enable-iconv --enabl
e-libass --enable-libbluray --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amr
wb --enable-libopenjpeg --enable-libopus --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libtheora --enab
le-libtwolame --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --
enable-libzimg --enable-lzma --enable-zlib --enable-gmp --enable-libvidstab --enable-libvorbis --enable-libvo-amrwbenc -
-enable-libmysofa --enable-libspeex --enable-libxvid --enable-libaom --enable-libmfx --enable-amf --enable-ffnvcodec --e
nable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec --enable-dxva2 --enable-avisynth
libavutil 56. 19.100 / 56. 19.100
libavcodec 58. 24.101 / 58. 24.101
libavformat 58. 17.103 / 58. 17.103
libavdevice 58. 4.101 / 58. 4.101
libavfilter 7. 26.100 / 7. 26.100
libswscale 5. 2.100 / 5. 2.100
libswresample 3. 2.100 / 3. 2.100
libpostproc 55. 2.100 / 55. 2.100
[mpeg2video @ 0000025ec4127e80] Invalid frame dimensions 0x0.
Last message repeated 9 times
[mpegts @ 0000025ec40fd680] start time for stream 0 is not set in estimate_timings_from_pts
[mpegts @ 0000025ec40fd680] start time for stream 5 is not set in estimate_timings_from_pts
[mpegts @ 0000025ec40fd680] PES packet size mismatch
Last message repeated 1 times
[mpegts @ 0000025ec40fd680] Could not find codec parameters for stream 7 (Unknown: none ([12][0][0][0] / 0x000C)): unkno
wn codec
Consider increasing the value for the 'analyzeduration' and 'probesize' options
[mpegts @ 0000025ec40fd680] Could not find codec parameters for stream 8 (Unknown: none ([5][0][0][0] / 0x0005)): unknow
n codec
Consider increasing the value for the 'analyzeduration' and 'probesize' options
[mpegts @ 0000025ec40fd680] Could not find codec parameters for stream 9 (Unknown: none ([11][0][0][0] / 0x000B)): unkno
wn codec
Consider increasing the value for the 'analyzeduration' and 'probesize' options
Input #0, mpegts, from 'D:\Crenova\sources\Tizen3\TiviconConnectTizenWebappPC\libav\capture_das_erste_131s_mpeg2.ts':
Duration: 00:02:11.44, start: 3980.301189, bitrate: 6822 kb/s
Program 10400
Program 10401
Program 10402
Program 10403
Program 10404
Program 10405
Program 10406
Program 10407
Program 10408
Program 10432
Program 10433
Program 10434
Program 10451
Program 10452
Program 10453
Program 10454
Program 10455
Program 10456
Program 10457
Program 10458
Program 10459
Program 10465
Program 10466
Program 10467
Program 10468
Program 10469
Program 10470
Program 28106
Stream #0:0[0x54]: Data: bin_data ([6][0][0][0] / 0x0006)
Stream #0:1[0x65]: Video: mpeg2video (Main) ([2][0][0][0] / 0x0002), yuv420p(tv, top first), 720x576 [SAR 64:45 DAR
16:9], 25 fps, 25 tbr, 90k tbn, 50 tbc
Stream #0:20x66: Audio: mp2 ([3][0][0][0] / 0x0003), 48000 Hz, stereo, fltp, 256 kb/s
Stream #0:30x67: Audio: mp2 ([3][0][0][0] / 0x0003), 48000 Hz, stereo, fltp, 192 kb/s (visual impaired) (desc
riptions)
Stream #0:40x68: Subtitle: dvb_teletext ([6][0][0][0] / 0x0006)
Stream #0:50x69: Subtitle: dvb_subtitle ([6][0][0][0] / 0x0006) (hearing impaired)
Stream #0:60x6a: Audio: ac3 ([6][0][0][0] / 0x0006), 48000 Hz, stereo, fltp, 448 kb/s
Stream #0:7[0x498]: Unknown: none ([12][0][0][0] / 0x000C)
Stream #0:8[0x816]: Unknown: none ([5][0][0][0] / 0x0005)
Stream #0:9[0x87b]: Unknown: none ([11][0][0][0] / 0x000B)
Program 28107
Program 28108
Program 28110
Program 28111
Program 28113
Unsupported codec with id 100359 for input stream 0
Unsupported codec with id 94215 for input stream 4
Unsupported codec with id 0 for input stream 7
Unsupported codec with id 0 for input stream 8
Unsupported codec with id 0 for input stream 9

Luke-HSKim · Answer 7 · Wed May 10 2023 22:06:29 GMT+0800 (China Standard Time)

it was captured from DVB-C live stream, so probably it has some errors. anyway, it was no problem to playback by vlc or other players.

As I tested other streams, it was stopped always with following error.

libav-3.11.5.1.2-default.simd.js:708 [mpeg2video @ 0x2d3380] Invalid frame dimensions 0x0.

Yahweasel · Answer 8 · Wed May 10 2023 23:20:05 GMT+0800 (China Standard Time)

libav.js is not VLC, it's ffmpeg. Do these files work in desktop ffmpeg? If not, the idea of getting them working here is hopeless.

Luke-HSKim · Answer 9 · Thu May 11 2023 00:37:30 GMT+0800 (China Standard Time)

i have tried with libavcodec, libavformat, and libavutil, and it could playback correctly.

When I tried at first time, i didn't check logs from ffmpeg libraries, and I checked the logs from pc after your comment. I found there is same "Invalid frame dimensions 0x0.".

Can I ignore some warnings or errors from libav.js?

logs from PC
[mpeg2video @ 000001F0180D19C0] Invalid frame dimensions 0x0.
[mpeg2video @ 000001F0180D19C0] Invalid frame dimensions 0x0.
[mpeg2video @ 000001F0180D19C0] Invalid frame dimensions 0x0.
[mpeg2video @ 000001F0180D19C0] Invalid frame dimensions 0x0.
[mpeg2video @ 000001F0180D19C0] Invalid frame dimensions 0x0.
[mpeg2video @ 000001F0180D19C0] Invalid frame dimensions 0x0.
[mpeg2video @ 000001F0180D19C0] Invalid frame dimensions 0x0.
[mpeg2video @ 000001F0180D19C0] Invalid frame dimensions 0x0.
[mpeg2video @ 000001F0180D19C0] Invalid frame dimensions 0x0.
[mpeg2video @ 000001F0180D19C0] Invalid frame dimensions 0x0.
[mpegts @ 000001F0180A19C0] Packet corrupt (stream = 1, dts = 358295526).
[mpegts @ 000001F0180A19C0] start time for stream 0 is not set in estimate_timings_from_pts
[mpegts @ 000001F0180A19C0] start time for stream 5 is not set in estimate_timings_from_pts
[mpegts @ 000001F0180A19C0] PES packet size mismatch
[mpegts @ 000001F0180A19C0] Packet corrupt (stream = 4, dts = 370027961).
[mpegts @ 000001F0180A19C0] PES packet size mismatch
[mpegts @ 000001F0180A19C0] Packet corrupt (stream = 6, dts = 370023587).
[mpegts @ 000001F0180A19C0] Could not find codec parameters for stream 7 (Unknown: none ([12][0][0][0] / 0x000C)): unknown codec
Consider increasing the value for the 'analyzeduration' (0) and 'probesize' (5000000) options
[mpegts @ 000001F0180A19C0] Could not find codec parameters for stream 8 (Unknown: none ([5][0][0][0] / 0x0005)): unknown codec
Consider increasing the value for the 'analyzeduration' (0) and 'probesize' (5000000) options
[mpegts @ 000001F0180A19C0] Could not find codec parameters for stream 9 (Unknown: none ([11][0][0][0] / 0x000B)): unknown codec
Consider increasing the value for the 'analyzeduration' (0) and 'probesize' (5000000) options
[mpegts @ 000001F0180A19C0] Packet corrupt (stream = 1, dts = 358295526).
[mpeg2video @ 000001F0180DF240] Invalid mb type in B-frame at 25 27
[mpeg2video @ 000001F0180DF240] Warning MVs not available
[mpeg2video @ 000001F0180DF240] concealing 45 DC, 45 AC, 45 MV errors in B frame
[mpegts @ 000001F0180A19C0] PES packet size mismatch
[mpegts @ 000001F0180A19C0] Packet corrupt (stream = 4, dts = 370027961).
[mpegts @ 000001F0180A19C0] PES packet size mismatch
[mpegts @ 000001F0180A19C0] Packet corrupt (stream = 6, dts = 370023587).
[mpeg2video @ 000001F0180DF240] Warning MVs not available
[mpeg2video @ 000001F0180DF240] concealing 225 DC, 225 AC, 225 MV errors in B frame

Yahweasel · Answer 10 · Thu May 11 2023 04:42:19 GMT+0800 (China Standard Time)

I actually forgot that I added this, but yes, ff_decode_multi supports ignoring errors. I think the following replacement for the ff_decode_multi line in demo.html might do what you want:

const frames = await libav.ff_decode_multi(
    c, pkt, frame, [vPacket], {
    fin: (res === libav.AVERROR_EOF && vIdx === vPackets.length - 1),
    ignoreErrors: true
    }
);

Luke-HSKim · Answer 11 · Thu May 11 2023 04:58:22 GMT+0800 (China Standard Time)

Thank you for your answer! Now it works! But i faced following message. :(

Luke-HSKim · Answer 12 · Thu May 11 2023 05:36:16 GMT+0800 (China Standard Time)

i could see video after disabling Scaling part and adding to avoid wrong frames like following.

But picture is black and white and ratio is completely wrong.

Any advice?

Yahweasel · Answer 13 · Thu May 11 2023 05:52:45 GMT+0800 (China Standard Time)

See #21 (comment) . This is why the video libavs enable swscale. It does pixel format conversion. What you're looking at is data that's not RGB.

Luke-HSKim · Answer 14 · Thu May 11 2023 20:44:03 GMT+0800 (China Standard Time)

I found that frame.channels is not defined, and it causes wrong behavior at scaling functions. I fixed it by converting YCrCb to RGBA and no scaling.
Thank you for your kind support!