[Ffmpeg-devel] [ppm @ 0x40415168]picture size invalid (1x0)

[Víctor Paesa]

> Hi,
>
>> I tried to pipe a stream of ppm file into ffmpeg to create a video.
>> However, the following command sequence causes ffmpeg to complain about
>> an invalid picture size and produces a video which is garbled after some
>> time.
>>
>>> convert -size 160x128 -depth 8 xc:white white.ppm
>>> i=0
>>> while [ $((i<10000)) == 1 ]; do let i=$((i+1)); cat white.ppm ; done |
>> ffmpeg -f image2pipe -vcodec ppm -i - -s 160x128 -r 25 -b 90 -f
>> mpeg2video -aspect 4:3 -y out.mpv
>>
>
> I run into a similar problem that was solved by using
> pnmtopnm (part of the Netpbm tools) in front of ffmpeg.
>
> Could you please attempt to use:
>
> convert -size 160x128 -depth 8 xc:white white.ppm
> i=0
> while [ $((i<10000)) == 1 ]
> do
>   let i=$((i+1))
>   cat white.ppm
> done | \
> pnmtopnm | \
> ffmpeg -f image2pipe -vcodec ppm -i - \
>   -s 160x128 -r 25 -b 90 -f mpeg2video -aspect 4:3 -y out.mpv
>
>

Actually I noticed this in your log

>Output #0, mpeg2video, to 'out.mpv':
>  Stream #0.0: Video: ppm, rgb24, 160x128, q=2-31, 90 kb/s, 25.00 fps(c

Try specifying the codec, -vcodec mpeg2video, and maybe setting -r at input:


convert -size 160x128 -depth 8 xc:white white.ppm
i=0
while [ $((i<100)) == 1 ]
do
   let i=$((i+1))
   cat white.ppm
done | \
pnmtopnm | \
ffmpeg -r 25 -f image2pipe -vcodec ppm -i - \
   -s 160x128 -r 25 -b 90 \
   -f mpeg2video -vcodec mpeg2video -aspect 4:3 -y out.mpv

Regards,
V?ctor