On Sat, Aug 08, 2015 at 18:16:13 +0530, Robin Lery wrote: > Yes, thank you. I understand now. However I tried doing two pass multiple > output with one input like this: > > ffmpeg -i mi6.mp4 \ > -codec:v libx264 -tune zerolatency -profile:v main -preset medium -b:v > 1000k -maxrate 1000k -bufsize 10000k -s hd720 -threads 0 -pix_fmt yuv420p > -pass 1 -passlogfile unique_id-hd720 -an -f mp4 /dev/null \ > -codec:v libx264 -tune zerolatency -profile:v baseline -level 3.0 > -preset medium -b:v 250k -maxrate 250k -bufsize 2500k -vf > scale="trunc(oh*a/2)*2:360" -threads 0 -pix_fmt yuv420p -movflags > +faststart -pass 1 -passlogfile unique_id-360 -an -f mp4 /dev/null && \ > -codec:v libx264 -tune zerolatency -profile:v main -preset medium -b:v > 1000k -maxrate 1000k -bufsize 10000k -s hd720 -threads 0 -pix_fmt yuv420p > -pass 2 -passlogfile unique_id-hd720 -codec:a libfdk_aac -movflags > +faststart output/mi6-poty-720.mp4 \ > -codec:v libx264 -tune zerolatency -profile:v baseline -level 3.0 > -preset medium -b:v 250k -maxrate 250k -bufsize 2500k -vf > scale="trunc(oh*a/2)*2:360" -threads 0 -pass 2 -passlogfile unique_id-360 > -codec:a libfdk_aac -pix_fmt yuv420p -movflags +faststart > output/mi6-poty-360.mp4
No no no! That's _one_ ffmpeg command, right? You're now tring to do pass 1 and pass 2 in parallel. You're missing the point: ffmpeg _must_ be called twice (i.e. two passes) using the same input file _in succession_. The first pass creates the log file, the second pass uses that log file (_after_ it has been created by the first pass) to do the final encode. > When I run this command first I get this: > File '/dev/null' already exists. Overwrite ? [y/N] y > File '/dev/null' already exists. Overwrite ? [y/N] y ffmpeg doesn't know that this is a "special" file the contents of which may be overwritten, so it does ask. > Afterward there's two file with the specified name, but the file size is 0. > What's going on? You mean name_s_. Reason is above: You are not doing two successive passes. Moritz _______________________________________________ ffmpeg-user mailing list [email protected] http://ffmpeg.org/mailman/listinfo/ffmpeg-user
