On Sun, Feb 28, 2021 at 5:31 PM Ian Pilcher <arequip...@gmail.com> wrote:
> On 2/26/21 9:52 PM, pdr0 wrote: > > Different timebase means there is potential to compare different frames. > > > > Use settb > > > > ffmpeg -framerate 60000/1001 -i lossless.mkv -start_number 0 -framerate > > 60000/1001 -i source/%06d.tif -t 00:01:00 -lavfi > > > "[0:v]settb=1/AVTB,setpts=PTS-STARTPTS[main];[1:v]settb=1/AVTB,setpts=PTS-STARTPTS[ref];[main][ref]ssim" > > -f null - > > That seems to work. It gets rid of the "not matching timebases" > warning. It does cause the duration option (-t 00:01:00) to not work, > but I was able to use the "-frames:v" option instead. (In fact, I don't > need specify the framerate of the image sequence at all.) > > $ ffmpeg -i lossless.mkv -start_number 0 -i source/%06d.tif -frames:v > 3596 -lavfi > "[0:v]settb=1/AVTB,setpts=PTS-STARTPTS[main];[1:v]settb=1/AVTB,setpts=PTS-STARTPTS[ref];[main][ref]ssim" > > -f null - > ... > Input #0, matroska,webm, from 'lossless.mkv': > Metadata: > ENCODER : Lavf58.45.100 > Duration: 00:00:59.99, start: 0.000000, bitrate: 1223104 kb/s > Stream #0:0: Video: huffyuv (HFYU / 0x55594648), bgr0, 1440x1080, > 59.94 fps, 59.94 tbr, 1k tbn, 1k tbc (default) > Metadata: > ENCODER : Lavc58.91.100 huffyuv > DURATION : 00:00:59.994000000 > Input #1, image2, from 'source/%06d.tif': > Duration: 04:17:10.96, start: 0.000000, bitrate: N/A > Stream #1:0: Video: tiff, rgb24, 1440x1080, 25 tbr, 25 tbn, 25 tbc > ... > [Parsed_ssim_4 @ 0x562a600ac780] SSIM R:0.999888 (39.506142) > G:0.999889 (39.531716) B:0.999887 (39.466715) All:0.999888 (39.501442) > > So this gets me to the same result that I got when I compared the > derived PNG image sequence to the original TIFF sequence. > > $ ffmpeg -start_number 0 -i lossless/%06d.png -start_number 0 -i > source/%06d.tif -frames:v 3596 -filter_complex ssim -f null - > ... > [Parsed_ssim_0 @ 0x5630c77ad440] SSIM R:0.999888 (39.506142) > G:0.999889 (39.531716) B:0.999887 (39.466715) All:0.999888 (39.501442) > > Now that I know about the -frames:v option, I decided to try omitting > the last frame from the comparison. > > $ ffmpeg -start_number 0 -i lossless/%06d.png -start_number 0 -i > source/%06d.tif -frames:v 3595 -filter_complex ssim -f null - > ... > [Parsed_ssim_0 @ 0x560797482440] SSIM R:1.000000 (inf) G:1.000000 > (inf) B:1.000000 (inf) All:1.000000 (inf) > > $ ffmpeg -i lossless.mkv -start_number 0 -i source/%06d.tif -frames:v > 3595 -lavfi > "[0:v]settb=1/AVTB,setpts=PTS-STARTPTS[main];[1:v]settb=1/AVTB,setpts=PTS-STARTPTS[ref];[main][ref]ssim" > > -f null - > ... > [Parsed_ssim_4 @ 0x5571f0a97780] SSIM R:1.000000 (inf) G:1.000000 > (inf) B:1.000000 (inf) All:1.000000 (inf) > > That gets me the expected score. > > I don't understand why I have to omit the final frame. Both ImageMagick > and ffmpeg show the images as identical. > > $ compare -metric AE lossless/003595.png source/003595.tif /tmp/diff.png > 0 > > $ ffmpeg -i lossless/003595.png -i source/003595.tif -filter_complex > ssim -f null - > ... > [Parsed_ssim_0 @ 0x561a6aae1540] SSIM R:1.000000 (inf) G:1.000000 > (inf) B:1.000000 (inf) All:1.000000 (inf) > > This is definitely good enough for my purposes, however. I'm going to > declare victory and move on. > Try ssim=shortest=1 Most likely inputs have not same number of frames. > > Thanks for your help! > > -- > ======================================================================== > In Soviet Russia, Google searches you! > ======================================================================== > > _______________________________________________ > 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".
