[FFmpeg-user] Reducing image2pipe png decoder latency

[Carl Eugen Hoyos]

Am Mi., 11. Dez. 2019 um 14:24 Uhr schrieb Maxim Khitrov <max at mxcrypt.com>:

> ffmpeg -f image2pipe -avioflags direct -fflags nobuffer -fpsprobesize
> 0 -framerate 30 -probesize 22023 -an -c:v mjpeg -pixel_format yuvj420p
> -video_size 1280x720 -i \\.\pipe\ffmpeg-OTdHYsp8CvAJMsnK.0 -f
> image2pipe -avioflags direct -fflags nobuffer -fpsprobesize 0
> -framerate 30 -probesize 5811 -an -c:v png -pixel_format rgba
> -video_size 640x360 -i \\.\pipe\ffmpeg-OTdHYsp8CvAJMsnK.1
> -filter_complex
> 'sws_flags=fast_bilinear;[1:v]format=yuva420p[f1];[f1][0:v]scale2ref=w=iw:h=ih[s1][s0];[s0][s1]overlay=eval=init[v0]'
> -filter_threads 1 -map '[v0]' -c:v libx264 -profile:v high -preset
> superfast -tune zerolatency -x264-params
> keyint=90:min-keyint=30:bframes=0 -intra-refresh 1 -r 30 -thread_type
> slice -f mpegts -
>
> [image2pipe @ 000001f9e6b9eec0] Stream #0: not enough frames to
> estimate rate; consider increasing probesize
> Input #0, image2pipe, from '\\.\pipe\ffmpeg-Mb7lgdkRbbyjzpol.0':
>   Duration: N/A, bitrate: N/A
>     Stream #0:0: Video: mjpeg, yuvj420p(bt470bg/unknown/unknown),
> 1280x720, 30 tbr, 30 tbn, 30 tbc
> [image2pipe @ 000001f9e6bcc5c0] Stream #0: not enough frames to
> estimate rate; consider increasing probesize
> Input #1, image2pipe, from '\\.\pipe\ffmpeg-Mb7lgdkRbbyjzpol.1':
>   Duration: N/A, bitrate: N/A
>     Stream #1:0: Video: png, rgba(pc), 640x360, 30 tbr, 30 tbn, 30 tbc
> Stream mapping:
>   Stream #0:0 (mjpeg) -> scale2ref:ref
>   Stream #1:0 (png) -> format
>   overlay -> Stream #0:0 (libx264)
> [libx264 @ 000001f9e6ba1dc0] using cpu capabilities: MMX2 SSE2Fast
> SSSE3 SSE4.2 AVX FMA3 BMI2 AVX2
> [libx264 @ 000001f9e6ba1dc0] profile High, level 3.1, 4:2:0, 8-bit
> Output #0, mpegts, to 'pipe:':
>   Metadata:
>     encoder         : Lavf58.35.100
>     Stream #0:0: Video: h264 (libx264), yuvj420p(pc), 1280x720,
> q=-1--1, 30 fps, 90k tbn, 30 tbc (default)
>     Metadata:
>       encoder         : Lavc58.62.100 libx264
>     Side data:
>       cpb: bitrate max/min/avg: 0/0/0 buffer size: 0 vbv_delay: N/A
> [mjpeg @ 000001f9e6bcaf00] error count: 64
> [mjpeg @ 000001f9e6bcaf00] error y=2 x=1
> [mjpeg @ 000001f9e6bcaf00] mjpeg_decode_dc: bad vlc: 0:0
> (000001f9e6bcb5c8)bits/s speed=0.968x
> [mjpeg @ 000001f9e6bcaf00] error dc
> [mjpeg @ 000001f9e6bcaf00] error y=44 x=57
> [mjpeg @ 000001f9e6bcaf00] mjpeg_decode_dc: bad vlc: 0:0
> (000001f9e6bcb5c8)bits/s speed=0.975x
> [mjpeg @ 000001f9e6bcaf00] error dc
> [mjpeg @ 000001f9e6bcaf00] error y=44 x=68
> frame=  310 fps= 30 q=23.0 Lsize=    1663kB time=00:00:10.33
> bitrate=1318.2kbits/s speed=0.998x
> video:1552kB audio:0kB subtitle:0kB other streams:0kB global
> headers:0kB muxing overhead: 7.149707%
> [libx264 @ 000001f9e6ba1dc0] frame I:1     Avg QP: 5.79  size: 10606
> [libx264 @ 000001f9e6ba1dc0] frame P:309   Avg QP: 9.00  size:  5108
> [libx264 @ 000001f9e6ba1dc0] mb I  I16..4: 92.3%  0.2%  7.5%
> [libx264 @ 000001f9e6ba1dc0] mb P  I16..4: 82.6%  1.4%  1.4%  P16..4:
> 6.9%  0.0%  0.0%  0.0%  0.0%    skip: 7.8%
> [libx264 @ 000001f9e6ba1dc0] 8x8 transform intra:1.6% inter:94.1%
> [libx264 @ 000001f9e6ba1dc0] coded y,uvDC,uvAC intra: 1.5% 4.3% 3.0%
> inter: 26.6% 35.7% 5.2%
> [libx264 @ 000001f9e6ba1dc0] i16 v,h,dc,p: 78% 11% 10%  0%
> [libx264 @ 000001f9e6ba1dc0] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu:  4%  5%
> 45% 40%  0%  0%  0%  0%  6%
> [libx264 @ 000001f9e6ba1dc0] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 61% 19%
> 13%  1%  1%  1%  1%  1%  1%
> [libx264 @ 000001f9e6ba1dc0] i8c dc,h,v,p: 72% 12% 16%  0%
> [libx264 @ 000001f9e6ba1dc0] Weighted P-Frames: Y:1.0% UV:0.0%
> [libx264 @ 000001f9e6ba1dc0] kb/s:1230.27

There is something strange about your console output (many lines
seem to be missing), if this is a patched binary of FFmpeg, please
ask for support wherever you found the binary.

Carl Eugen