Dear mailing list members, When converting/rendering a SMIL animated SVG (as eg: https://github.com/romangrothausmann/aniMakefileSVG/blob/gh-pages/all.dot.Ma...) into a video with MP4Client from gpac I've trouble to find the right parameters to encode the resulting raw AVI on the fly to e.g. MP4 with either mencoder oder ffmpeg (apparently not possible directly with gpac tools, https://github.com/gpac/gpac/issues/543) All works well when encoding the full AVI (e.g. all.dot.Make.avi.bz2, as can be found here: https://gist.github.com/romangrothausmann/15bd4cc74395ab3e01cc54e261b35a8e): MP4Client -no-audio -size 100x1000 -avi 0-10 -fps 25 all.dot.Make.svg -out all.dot.Make.avi ffmpeg -y -f rawvideo -pix_fmt bgr24 -r 25 -s 100x1000 -i all.dot.Make.avi file.mp4 mencoder -cache 8000 -nosound -o test.mp4 -ovc x264 -fps 25 -demuxer rawvideo -rawvideo w=100:h=1000:fps=25.000:format=bgr24 all.dot.Make.avi The AVI can easily reach up to 100GB for longer and bigger SVG animations. Therefore I tried to encode the same data from a pipe or fifo. However, it results in a "moving" animation (that ought to be stationary) with flickering colors: mkfifo fifo.avi MP4Client -no-audio -size 100x1000 -avi 0-10 -fps 25 all.dot.Make.svg -out fifo.avi & ffmpeg -y -f rawvideo -pix_fmt bgr24 -r 25 -s 100x1000 -i fifo.avi file.mp4 mencoder -cache 8000 -nosound -o test.mp4 -ovc x264 -fps 25 -demuxer rawvideo -rawvideo w=100:h=1000:fps=25.000:format=bgr24 fifo.avi Also using cat for simulating piping does not work: cat all.dot.Make.avi | mencoder -cache 8000 -nosound -o test.mp4 -ovc x264 -fps 25 -demuxer rawvideo -rawvideo w=100:h=1000:fps=25.000:format=bgr24 - It seems as if an extra pixel column per frame moves the image but changing the size by +/- 1 pixel did not help. I expect the AVI is not completely raw but contains some bytes in between the frames. If so, how can I skip these or get the same result as obtained without piping? Many thanks for any help or hints. Roman