I noticed that videos that I render with HEVC codec looks terrible in Kdenlive. So, while rendering the video, I ran a ps -ef|grep kdenlive. This is the output line. /usr/bin/kdenlive_render -erase -pid:19993 /usr/bin/melt atsc_1080p_25 avformat - /tmp/kdenlive_rendering_u19993.mlt.mlt /data/DigiKam/Video Clips Uncompressed/Home/2015/10-17 Kuiseb Camp/Sunset Time Lapse x265.mp4 properties=x265-medium -x265-params=crf=%quality ab=160k threads=16 real_time=-1 Interestingly, the quality setting is not passed to the renderer, instead it's passed as "-x265-params=crf=%quality" Instead of "-x265-params=crf=26" ( the default ) What this means is that I am unable to change the quality of the output Reproducible: Always Steps to Reproduce: 1. Render a video using the HEVC format. 2. In a terminal, run ps -ef | grep kdenlive 3. Look at the quality setting in the command line Actual Results: Video rendered to pretty low quality setting. Expected Results: Video rendered to intended quality setting.
Git commit 0d94bf454665f897c59307ed89ce723b0d97db8c by Jean-Baptiste Mardelle. Committed on 21/10/2015 at 09:20. Pushed by mardelle into branch 'master'. Fix x265 variable parameter incorrectly set M +3 -3 src/dialogs/renderwidget.cpp http://commits.kde.org/kdenlive/0d94bf454665f897c59307ed89ce723b0d97db8c
Git commit 3cfadbe7e3ee78d8a859d699a1b0f46d28346d00 by Vincent Pinon, on behalf of Jean-Baptiste Mardelle. Committed on 03/11/2015 at 21:14. Pushed by vpinon into branch 'Applications/15.08'. Fix x265 variable parameter incorrectly set M +3 -3 src/dialogs/renderwidget.cpp http://commits.kde.org/kdenlive/3cfadbe7e3ee78d8a859d699a1b0f46d28346d00
The requested quality setting is now on the command line. However, it is still being ignored, and the video is being rendered at default quality level. When I encode 1080p25 with a quality setting of 20 in HEVC, I expect a bitrate of about 4000-5000kb/s, but I get 400kb/s output, and horrible looking video.
Aha... I finally made some sense of the melt help. Looks like the x265 parameters are set pretty much the same as x264, at least as far as melt is concerned. The following profile produces video at the proper quality settings: properties=x265-medium crf=%quality ab=%audiobitrate+'k' The list of quality settings can also be expanded to include 20, which is nearly lossless, and half the data rate of x264 crf 20.
Git commit 59601a86174d1f32e7593cf6d48e15f12c9e54af by Jean-Baptiste Mardelle. Committed on 16/11/2015 at 20:05. Pushed by mardelle into branch 'Applications/15.12'. Update H.265 HEVC rendering profile, patch by Evert Vorster M +2 -2 data/profiles.xml http://commits.kde.org/kdenlive/59601a86174d1f32e7593cf6d48e15f12c9e54af
*** Bug 363446 has been marked as a duplicate of this bug. ***
This has been working properly for quite a while now.