On 17/09/15 23:45, Dave Rice wrote: > Hi, > >> On Sep 14, 2015, at 11:56 PM, Etienne Desautels >> <etienne.desaut...@gmail.com> wrote: >> >> Hi, >> >> I will start using FFV1 to archive video for a museum and I will like to >> know what's the best settings to get smaller files. I will use version 3 >> with checksums. From the few tests I did I found that those settings were >> the best for smaller files: >> - coder 1 >> - context 0 >> - g 1 > > I believe using -g 1 would require more size than not. On the other hand this > is usually one of the parameters for ffv1 I recommend the most as it > increases the resilience of the file which is particularly relevant for > archival use. > >> - slices 4 >> >> I really don't know what to think about context size. Somewhere else I saw >> that large context create smaller files. But in my tests that was the >> inverse. >> >> I also tried 2 pass without any success. The final file were exactly the >> same size as the one created with 1 pass. And the log of the 2 pass was >> filled only with 0 except for the last number that was something like 843? > > Can you show your process? Have you tried the directions according to the > wiki? http://trac.ffmpeg.org/wiki/Encode/FFV1 > > If the file size is a bigger issue than the options used, you could examine > the test suite results at > http://download.das-werkstatt.com/pb/mthk/ffv1_stats/latest/ > <http://download.das-werkstatt.com/pb/mthk/ffv1_stats/latest/>. The labels > such as v3c01s4 document the version (3), coder (0), context (1), and slices > (4). > Best Regards, > Dave Rice > > >> Any advices? >> >> Regards, >> Etienne Desautels >> _______________________________________________
I don't want to interfere but only to understand the parameters. 2nd link, FFv1 results GOP=1 vs. GOP=300 Documentation says: Slices -slices 4, 6, 9, 12, 16, 24, 30 Each frame is split into this number of slices. This affects multithreading performance, as well as filesize: Increasing the number of slices might speed up performance, but also increases the filesize. What I understand in the result, ie: first line v3c11s4: -16.68% means the resulting file is smaller by this value compared to the original v3c11s30: -17.33% means the resulting file is smaller by this value compared to the original Conclusion: s30 has a smaller filesize than with s4 (for all the lines) => opposite what says the documentation. Am I right? BTW what are the default values of all these parameters in the first link? I can't find any user documentation, I mean not too hard to understand. _______________________________________________ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-user