Recherche avancée
Autres articles (22)
-
L’utiliser, en parler, le critiquer
10 avril 2011La première attitude à adopter est d’en parler, soit directement avec les personnes impliquées dans son développement, soit autour de vous pour convaincre de nouvelles personnes à l’utiliser.
Plus la communauté sera nombreuse et plus les évolutions seront rapides ...
Une liste de discussion est disponible pour tout échange entre utilisateurs. -
Encoding and processing into web-friendly formats
13 avril 2011, parMediaSPIP automatically converts uploaded files to internet-compatible formats.
Video files are encoded in MP4, Ogv and WebM (supported by HTML5) and MP4 (supported by Flash).
Audio files are encoded in MP3 and Ogg (supported by HTML5) and MP3 (supported by Flash).
Where possible, text is analyzed in order to retrieve the data needed for search engine detection, and then exported as a series of image files.
All uploaded files are stored online in their original format, so you can (...) -
Supporting all media types
13 avril 2011, parUnlike most software and media-sharing platforms, MediaSPIP aims to manage as many different media types as possible. The following are just a few examples from an ever-expanding list of supported formats : images : png, gif, jpg, bmp and more audio : MP3, Ogg, Wav and more video : AVI, MP4, OGV, mpg, mov, wmv and more text, code and other data : OpenOffice, Microsoft Office (Word, PowerPoint, Excel), web (html, CSS), LaTeX, Google Earth and (...)
Sur d’autres sites (4975)
-
Using ffmpeg alphamerge to mask two images before calculating similarity index [closed]
12 août 2024, par user2814357I'm working on a script that removes duplicate frames from images stored on disk. I need to ignore certain irrelevant parts of the images.


The following ffmpeg command line should work, but it returns the same SSIM statistics as without mask.


ffmpeg -i 1.webp -i 2.webp -i mask.png -filter_complex \
"[0][2]alphamerge[img1]; \
 [1][2]alphamerge[img2]; \
 [img1]format=yuva420p[masked1]; \
 [img2]format=yuva420p[masked2]; \
 [masked1][masked2]ssim=stats_file=-" -f null -


Example output :


[Parsed_ssim_4 @ 0x7fb76b70ff00] SSIM Y:0.829392 (7.680003) U:0.987882 (19.165656) V:0.993201 (21.675403) All:0.883108 (9.322165)
[out#0/null @ 0x7fb76c604700] video:0KiB audio:0KiB subtitle:0KiB other streams:0KiB global headers:0KiB muxing overhead: unknown
frame= 1 fps=0.0 q=-0.0 Lsize=N/A time=00:00:00.04 bitrate=N/A speed=0.602x 



Result is the same with
ffmpeg -i 1.webp -i 2.webp -lavfi ssim=stats_file=- -f null -.

[Parsed_ssim_0 @ 0x7f9c0cf06d80] SSIM Y:0.829392 (7.680003) U:0.987882 (19.165656) V:0.993201 (21.675403) All:0.883108 (9.322165)
[out#0/null @ 0x7f9c0da08e80] video:0KiB audio:0KiB subtitle:0KiB other streams:0KiB global headers:0KiB muxing overhead: unknown


This is weird because the masked output files look as expected if I output them with :


ffmpeg -i 1.webp -i 2.webp -i mask.png -filter_complex \
"[0][2]alphamerge[img1]; \
 [1][2]alphamerge[img2]; \
 [img1]format=yuva420p[masked1]; \
 [img2]format=yuva420p[masked2]" \
-map "[masked1]" masked_1.webp \
-map "[masked2]" masked_2.webp


Does anyone know what the right syntax would be for getting the SSIM values from a single command using a mask ?


Side note : If I use
-map "[masked1]" masked_1.jpgit outputs the original picture, not the masked one. Could there be a problem in the ffmpeg pipeline ?

Thank you very much !


-
av_vdpau_get_profile : mask out H.264 intra profile flag
4 mars 2014, par Rémi Denis-Courmont -
avcodec/ac3dec : Fix shift signedness in mask creation
21 septembre 2018, par Michael Niedermayeravcodec/ac3dec : Fix shift signedness in mask creation
Fixes : 9924/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_EAC3_fuzzer-5473421772193792
Fixes : left shift of 1 by 63 places cannot be represented in type 'long long'Found-by : continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by : Michael Niedermayer <michael@niedermayer.cc>
Syndiquer tout le site
