[FFmpeg-trac] #2367(undetermined:new): input_format / -pixel_format => libv4l2: error dequeuing buf: Resource temporarily unavailable

FFmpeg trac at avcodec.org
Tue Mar 19 18:17:33 CET 2013


#2367: input_format / -pixel_format => libv4l2: error dequeuing buf: Resource
temporarily unavailable
--------------------------------+----------------------------------------
             Reporter:  MrNice  |                    Owner:
                 Type:  defect  |                   Status:  new
             Priority:  normal  |                Component:  undetermined
              Version:  1.1.3   |               Resolution:
             Keywords:  v4l2    |               Blocked By:
             Blocking:          |  Reproduced by developer:  0
Analyzed by developer:  0       |
--------------------------------+----------------------------------------

Comment (by MrNice):

 I found out that the "invalid, clipping error" is related to the audio,
 IMHO.
 I tried recording 1 minute with the command:
 ffmpeg -debug 1 -f alsa -ac 2 -channel_layout stereo -i hw:0,0 -f v4l2
 -channel 1 -input_format yuyv422 -i /dev/video0 -map 0:a -map 1:v -c:a
 '''????''' -c:v ffv1 /Store3/Test/T`date +%Y%m%d_%H%M`.avi
 with ???? the following;
 flac (but players can't read it)
 ac3
 mp3
 I had no error at all when recording 1mn these 3,
 but a constant 30 seconds audio lateness (30s at the beginning and still
 30s after 1mn)

 With
 mp2 ==> I had clipping after 23 seconds recording and had 20 seconds more
 lateness(30s+20s=50s) when reading. The message was in yellow colour
 instead of green.
 [avi @ 0x23fde00] st:0 PTS: 954 DTS: 954 < 962 invalid, clipping
 *** drop!

 with
 pcm_alaw  ==> immediate error green
 pcm_f32le  ==> immediate error green
 pcm_f64le  ==> immediate error green
 pcm_mulaw  ==> immediate error green
 pcm_s16le  ==> immediate error green
 pcm_s24le  ==> immediate error green
 pcm_u8  ==> immediate error green
 and a constant 30 seconds lateness (30s at the beginning and still 30s
 after 1mn)
 There is no drop unlike with mp2 above.
 Tested reading with VLC and MPlayer.

 With the command
 ffmpeg -debug 1 -f alsa -ac 2 -channel_layout stereo -i hw:0,0 -f v4l2
 -channel 1 -input_format yuyv422 -i /dev/video0 -map 0:a -map 1:v -c:a
 pcm_s16le -c:v ffv1 /Store3/Test/T`date +%Y%m%d_%H%M`'''.mkv'''

 I had no error and a constant 30 seconds lateness (30s at the beginning
 and still 30s after 1mn)

 Maybe this will help.
 I'll ask if I can get a rebuilt.

-- 
Ticket URL: <https://ffmpeg.org/trac/ffmpeg/ticket/2367#comment:4>
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