On Fri, Dec 4, 2020 at 6:58 PM Michael Koch <astroelectro...@t-online.de> wrote:
> Am 04.12.2020 um 18:14 schrieb Paul B Mahol: > > On Wed, Dec 2, 2020 at 11:11 PM Michael Koch < > astroelectro...@t-online.de> > > wrote: > > > >> Am 01.12.2020 um 19:56 schrieb Michael Koch: > >>> Hello, > >>> > >>> there seem to be some problems in the v360 filter with "perspective" > >>> output. > >>> Tested with the latest Windows built, 2 days old. You can reproduce > >>> this with any equirectangular input image. > >>> > >>> ffmpeg -i equirectangular_test.png -lavfi v360=e:perspective -y > out1.png > >>> > >>> The output of the above command has two problems: > >>> -- The center of the input image is not mapped to the center of the > >>> output image. For most other projections the image center is preserved. > >>> -- The output is mirror reversed (which means you cannot read text). > >>> > >>> Both problems can be corrected with this workaround: > >>> > >>> ffmpeg -i equirectangular_test.png -lavfi > >>> v360=e:perspective:pitch=90:v_flip=1 -y out2.png > >>> > >>> Now I want to add a yaw rotation after the pitch rotation: > >>> > >>> ffmpeg -i equirectangular_test.png -lavfi > >>> v360=e:perspective:rorder=pyr:pitch=90:yaw=20:v_flip=1 -y out3.png > >>> > >>> But in the output you can see that a roll rotation was done. > >> Today I did for the very first time figure out how to compile ffmpeg. > >> The above problem can be solved by changing two lines in vf_v360.c > >> Sorry, I haven't yet figured out how to use git.One thing after the > >> other... > >> > >> Old version: > >> line 3136: vec[1] = sin_theta; > >> line 3137: vec[2] = cos_theta * cos_phi; > >> > >> New version: > >> line 3136: vec[1] = cos_theta * cos_phi; > >> line 3137: vec[2] = sin_theta; > >> > >> I'm not sure if lines 3139 to 3141 must also be changed. > >> > >> > > Good job! > > Please write a patch with correct authorship and send it to the devel > list. > > Fixing this for you was much more work than writing & sending patch will > be. > > lol, fixing this problem was done in 10 minutes. Since 3 days I'm trying > to figure out how git works. Git is the pure horror! I think I have the > patch file now, but now the next problem is that the subscription to the > ffmpeg-devel list doesn't work. > Just send it here then. > > Michael > > _______________________________________________ > 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".