I got those "unnecessary" args from https://trac.ffmpeg.org/wiki/Encode/YouTube They aren't important.
I think you might be mistaking CRF for CFR (constant frame rate). CRF is a measure of compression, it shouldn't drop and duplicate frames. frames. https://trac.ffmpeg.org/wiki/Encode/H.264#a1.ChooseaCRFvalue Anyways, in summary, here are commands with unnecessary args removed: My working command using detelecine (from prior message in thread with start_frame=3, pattern=2332), simplified: ffmpeg -i detelecine_input.mkv -c:v libx264 -c:a aac -vf "detelecine=start_frame=3:pattern=2332,drawtext=fontfile=Arial.ttf: text='%{frame_num}': start_number=0: x=(w-tw)/2: y=h-(2*lh): fontcolor=black: fontsize=20: box=1: boxcolor=white: boxborderw=5" detelecine_2332_simplified.mkv; (And my original question was why pattern=2332 was correct, since the pattern is visually to me just 23.) All my attempts to use fieldmatch+decimate causes frame 173 to be dropped and 174 to be duplicated. Example not working fieldmatch+decimate: ffmpeg -i detelecine_input.mkv -vf "fieldmatch,decimate,drawtext=fontfile=Arial.ttf: text='%{frame_num}': start_number=0: x=(w-tw)/2: y=h-(2*lh): fontcolor=black: fontsize=20: box=1: boxcolor=white: boxborderw=5" -c:v libx264 -c:a aac fieldmatch_decimate_simple.mkv And this was original source if you want to try yourself (12 MB, first 32 seconds truncated): https://www.mediafire.com/file/x4ly6moqb8ayfyy/detelecine_input.mkv/file On Wed, May 28, 2025 at 5:47 PM Mark Filipak <markfilipak.i...@gmail.com> wrote: > On 28/05/2025 19.18, Alex Xu wrote: > > Anyways, I tried: > > > > ffmpeg -i detelecine_input.mkv -vf > > "fieldmatch,decimate,drawtext=fontfile=Arial.ttf: text='%{frame_num}': > > start_number=0: x=(w-tw)/2: y=h-(2*lh): fontcolor=black: fontsize=20: > > box=1: boxcolor=white: boxborderw=5" -c:v libx264 -crf 18 -c:a aac -b:a > > 192k -pix_fmt yuv420p fieldmatch_decimate_only_no_r.mkv > > > > the issue of duplicated frames 174+175 and skipped 173. > > So, frame 173 was dropped, and frame 174 was repeated. I think that may > have resulted from "-crf 18". > > > In case you missed it, my test file was in the first message of the > chain. > > And using the detelecine filter got me the right result (with wrong > params?) > > Yes, the 'detelecine' filter will give you correct results for video > that's been statically and > correctly telecined: no variations, clean joins of the VOBs, if > applicable. But > 'fieldmatch'+'decimate' can be configured exactly that way. In contrast > 'fieldmatch' is a lot smarter. > > I hope you don't mind that I reformatted your commands. > > for i in 0 1 2 3 4; do > for j in 23 2332; do > ffmpeg^ > -i detelecine_input.mkv^ > -c:v libx264^ > -crf 18^ <== trouble? > -c:a aac^ > -b:a 192k^ <== why? > -pix_fmt yuv420p^ <== unnecessary > -vf^ > "detelecine=start_frame=$i:pattern=$j" > $i$j.mkv; > done > done > > I see what you're doing. By the way, which $i$j.mkv was the best? > > Your latest: > > set _DETELECINE_=fieldmatch,decimate > set _SHOW_N_=drawtext=fontfile=Arial.ttf^ > :text='%{frame_num}'^ > :start_number=0^ > :x=(w-tw)/2:y=h-(2*lh)^ > :fontcolor=black:fontsize=20^ > :box=1:boxcolor=white:boxborderw=5 > ffmpeg^ > -i detelecine_input.mkv^ > -vf^ > "%_DETELECINE_%,%_SHOW_N_%"^ > -c:v libx264^ > -crf 18^ <== trouble? > -c:a aac^ > -b:a 192k^ <== why? > -pix_fmt yuv420p^ <== unnecessary > fieldmatch_decimate_only_no_r.mkv > > By the way, I send about 30 options directly to x264 via '-x264-params', > none of which is 'crf'. My > videos are the highest quality and the smallest files ever. > > _______________________________________________ > ffmpeg-user mailing list > ffmpeg-user@ffmpeg.org > https://ffmpeg.org/mailman/listinfo/ffmpeg-user > > To unsubscribe, visit link above, or email > ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe". > _______________________________________________ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
