John Van Sickle <[email protected]> added the comment:
Sorry, I don't think my first patch was created correctly. Attaching a new one
plus adding myself to nosy list. Please let me know if I need to rework it.
Thanks,
relaxed
----------
nosy: +relaxed
____________________________________________________
FFmpeg issue tracker <[email protected]>
<https://roundup.ffmpeg.org/roundup/ffmpeg/issue269>
____________________________________________________
Index: doc/faq.texi
===================================================================
--- doc/faq.texi (revision 21029)
+++ doc/faq.texi (working copy)
@@ -316,7 +316,12 @@
Similarly, the yuv4mpegpipe format, and the raw video, raw audio codecs also
allow concatenation, and the transcoding step is almost lossless.
+When using multiple yuv4mpegpipe(s), the first line needs to be discarded from
+all but the first stream. This can be accomplished by piping through @code{tail}
+as seen below. Note that when piping through @code{tail} you must use command
+grouping, @co...@{ ;@}}, to background properly.
+
For example, let's say we want to join two FLV files into an output.flv file:
@example
@@ -329,7 +334,7 @@
ffmpeg -i input1.flv -vn -f u16le -acodec pcm_s16le -ac 2 -ar 44100 - > temp1.a < /dev/null &
ffmpeg -i input2.flv -vn -f u16le -acodec pcm_s16le -ac 2 -ar 44100 - > temp2.a < /dev/null &
ffmpeg -i input1.flv -an -f yuv4mpegpipe - > temp1.v < /dev/null &
-ffmpeg -i input2.flv -an -f yuv4mpegpipe - > temp2.v < /dev/null &
+...@{ ffmpeg -i input2.flv -an -f yuv4mpegpipe - < /dev/null | tail -n +2 > temp2.v ; @} &
cat temp1.a temp2.a > all.a &
cat temp1.v temp2.v > all.v &
ffmpeg -f u16le -acodec pcm_s16le -ac 2 -ar 44100 -i all.a \
