[FFmpeg-user] The device does not support the streaming I/O method.

[Thomas Seilund]

Carl Eugen Hoyos writes:

> Thomas Seilund <tps <at> netmaster.dk> writes:
>
>> --enable-x11grab
>
> Completely unrelated:
> --enable-x11grab is not necessary anymore, the new
> xcb input device is auto-detected by configure.
>
>>          return AVPROBE_SCORE_EXTENSION / 2 + 1;
>
> This corresponds to "return 26;" (I think).
> Could you test if a lower value than 26 helps?
> (You could first test 0, then 13 and so on...)
>
>> I did do make and make install
>
> I should add that I absolutely never install:
> At least for this test, you can run ./ffmpeg
> from the build directory.
>
> Thank you!
>
> Carl Eugen
>
>
> _______________________________________________
> ffmpeg-user mailing list
> ffmpeg-user at ffmpeg.org
> http://ffmpeg.org/mailman/listinfo/ffmpeg-user


Hi Carl

Thanks for the advice.


It works fine when "static int v4l2_read_probe(AVProbeData *p)" returns 0

tps at t420:~/data/data/ffmpeg$ ./ffmpeg -y -i /dev/video1 -c copy -f mpegts  
ffmpeg.ts
ffmpeg version N-69238-g2699a37 Copyright (c) 2000-2015 the FFmpeg  
developers
   built on Jan 26 2015 18:39:06 with gcc 4.8 (Ubuntu 4.8.2-19ubuntu1)
   configuration: --enable-gpl --enable-libmp3lame --enable-libvpx --enable- 
libx264 --enable-version3 --enable-libvorbis --enable-libfreetype --enable- 
libv4l2 --enable-libfdk-aac --enable-nonfree
   libavutil      54. 17.100 / 54. 17.100
   libavcodec     56. 20.100 / 56. 20.100
   libavformat    56. 19.100 / 56. 19.100
   libavdevice    56.  4.100 / 56.  4.100
   libavfilter     5.  8.101 /  5.  8.101
   libswscale      3.  1.101 /  3.  1.101
   libswresample   1.  1.100 /  1.  1.100
   libpostproc    53.  3.100 / 53.  3.100
Input #0, mpegts, from '/dev/video1':
   Duration: N/A, start: 0.390367, bitrate: N/A
   Program 1
     Stream #0:0[0x1011]: Video: h264 (Main) (HDMV / 0x564D4448),  
yuv420p(tv, bt709), 1280x720 [SAR 1:1 DAR 16:9], 50 fps, 50 tbr, 90k tbn,  
100 tbc
     Stream #0:1[0x1100]: Audio: aac (LC) ([15][0][0][0] / 0x000F), 48000  
Hz, stereo, fltp, 130 kb/s
Output #0, mpegts, to 'ffmpeg.ts':
   Metadata:
     encoder         : Lavf56.19.100
     Stream #0:0: Video: h264 (HDMV / 0x564D4448), yuv420p, 1280x720 [SAR  
1:1 DAR 16:9], q=2-31, 50 fps, 50 tbr, 90k tbn, 50 tbc
     Stream #0:1: Audio: aac ([15][0][0][0] / 0x000F), 48000 Hz, stereo, 130  
kb/s
Stream mapping:
   Stream #0:0 -> #0:0 (copy)
   Stream #0:1 -> #0:1 (copy)
Press [q] to stop, [?] for help
frame=  492 fps=101 q=-1.0 Lsize=    8784kB time=00:00:09.89  
bitrate=7269.4kbits/s
video:7927kB audio:158kB subtitle:0kB other streams:0kB global headers:0kB  
muxing overhead: 8.646630%
tps at t420:~/data/data/ffmpeg$



It works fine when "static int v4l2_read_probe(AVProbeData *p)" returns 13

tps at t420:~/data/data/ffmpeg$ ./ffmpeg -y -i /dev/video1 -c copy -f mpegts  
ffmpeg.ts
ffmpeg version N-69238-g2699a37 Copyright (c) 2000-2015 the FFmpeg  
developers
   built on Jan 26 2015 18:39:06 with gcc 4.8 (Ubuntu 4.8.2-19ubuntu1)
   configuration: --enable-gpl --enable-libmp3lame --enable-libvpx --enable- 
libx264 --enable-version3 --enable-libvorbis --enable-libfreetype --enable- 
libv4l2 --enable-libfdk-aac --enable-nonfree
   libavutil      54. 17.100 / 54. 17.100
   libavcodec     56. 20.100 / 56. 20.100
   libavformat    56. 19.100 / 56. 19.100
   libavdevice    56.  4.100 / 56.  4.100
   libavfilter     5.  8.101 /  5.  8.101
   libswscale      3.  1.101 /  3.  1.101
   libswresample   1.  1.100 /  1.  1.100
   libpostproc    53.  3.100 / 53.  3.100
Input #0, mpegts, from '/dev/video1':
   Duration: N/A, start: 0.390367, bitrate: N/A
   Program 1
     Stream #0:0[0x1011]: Video: h264 (Main) (HDMV / 0x564D4448),  
yuv420p(tv, bt709), 1280x720 [SAR 1:1 DAR 16:9], 50 fps, 50 tbr, 90k tbn,  
100 tbc
     Stream #0:1[0x1100]: Audio: aac (LC) ([15][0][0][0] / 0x000F), 48000  
Hz, stereo, fltp, 126 kb/s
Output #0, mpegts, to 'ffmpeg.ts':
   Metadata:
     encoder         : Lavf56.19.100
     Stream #0:0: Video: h264 (HDMV / 0x564D4448), yuv420p, 1280x720 [SAR  
1:1 DAR 16:9], q=2-31, 50 fps, 50 tbr, 90k tbn, 50 tbc
     Stream #0:1: Audio: aac ([15][0][0][0] / 0x000F), 48000 Hz, stereo, 126  
kb/s
Stream mapping:
   Stream #0:0 -> #0:0 (copy)
   Stream #0:1 -> #0:1 (copy)
Press [q] to stop, [?] for help
frame= 1071 fps= 65 q=-1.0 Lsize=   18975kB time=00:00:21.44  
bitrate=7250.1kbits/s
video:17123kB audio:342kB subtitle:0kB other streams:0kB global headers:0kB  
muxing overhead: 8.648141%
tps at t420:~/data/data/ffmpeg$



For the sake of the test I try to let "static int  
v4l2_read_probe(AVProbeData *p)" return 26 and now if fails

tps at t420:~/data/data/ffmpeg$ ./ffmpeg -y -i /dev/video1 -c copy -f mpegts  
ffmpeg.ts
ffmpeg version N-69238-g2699a37 Copyright (c) 2000-2015 the FFmpeg  
developers
   built on Jan 26 2015 18:39:06 with gcc 4.8 (Ubuntu 4.8.2-19ubuntu1)
   configuration: --enable-gpl --enable-libmp3lame --enable-libvpx --enable- 
libx264 --enable-version3 --enable-libvorbis --enable-libfreetype --enable- 
libv4l2 --enable-libfdk-aac --enable-nonfree
   libavutil      54. 17.100 / 54. 17.100
   libavcodec     56. 20.100 / 56. 20.100
   libavformat    56. 19.100 / 56. 19.100
   libavdevice    56.  4.100 / 56.  4.100
   libavfilter     5.  8.101 /  5.  8.101
   libswscale      3.  1.101 /  3.  1.101
   libswresample   1.  1.100 /  1.  1.100
   libpostproc    53.  3.100 / 53.  3.100
[video4linux2,v4l2 @ 0x31110e0] The device does not support the streaming  
I/O method.
/dev/video1: Function not implemented
tps at t420:~/data/data/ffmpeg$



Thanks

Thomas S