I wonder if "Settings|Preferences|Performance|Use HW Device" is meant to set both gpu accelerated decoding and encoding (rendering)?

and how does this possibly interact/work with selecting video preset, compression hwaccel methods or not?


Use HW Device has available 5 options: none, vaapi, vdpau, cuda, vulkan, while qsv is missing, reason?


I ran two av1_qsv rendering tests on Intel AlderLake/DG2 Using HW Device: None and vaapi respectively to exemplify this 

using the latest Cinelerra Infinity - built: Mar  1 2026 06:30:41


1) Settings|Preferences|Performance|Use HW Device: None

file: hdv09_04.m2t

compression
av1_qsv_8b420.mp4
# Requires specific GPU hardware encoding capability 
#  as well as required software implementation.
cin_pix_fmt=nv12
profile=main
# global_quality=25

libva info: VA-API version 1.23.0
libva info: Trying to open /usr/lib64/dri/iHD_drv_video.so
libva info: Found init function __vaDriverInit_1_22
libva info: va_openDriver() returns 0
libva info: VA-API version 1.23.0
libva info: Trying to open /usr/lib64/dri/iHD_drv_video.so
libva info: Found init function __vaDriverInit_1_22
libva info: va_openDriver() returns 0

Render::render_single: Session finished.
** rendered 5972 frames in 18.274 secs, 326.803 fps
audio0 pad 64 0 (64)

Fast and adequate quality/colors, although global quality may increase it somewhat.


2) Settings|Preferences|Performance|Use HW Device: vaapi (just to test)

file: hdv09_04.m2t

compression
av1_qsv_8b420.mp4
# Requires specific GPU hardware encoding capability 
#  as well as required software implementation.
cin_pix_fmt=nv12
profile=main
# global_quality=25

libva info: VA-API version 1.23.0
libva info: Trying to open /usr/lib64/dri/iHD_drv_video.so
libva info: Found init function __vaDriverInit_1_22
libva info: va_openDriver() returns 0
libva info: VA-API version 1.23.0
libva info: Trying to open /usr/lib64/dri/iHD_drv_video.so
libva info: Found init function __vaDriverInit_1_22
libva info: va_openDriver() returns 0

int FFVideoConvert::convert_picture_vframe(VFrame*, AVFrame*, AVFrame*):
Error retrieving data from GPU to CPU
file: /Videoklipp/AV1/hdv09_04.m2t
int FFVideoConvert::convert_picture_vframe(VFrame*, AVFrame*, AVFrame*):
Error retrieving data from GPU to CPU
file: /Videoklipp/AV1/hdv09_04.m2t
int FFVideoConvert::convert_picture_vframe(VFrame*, AVFrame*, AVFrame*):
Error retrieving data from GPU to CPU

file: /Videoklipp/AV1/hdv09_04.m2t
Render::render_single: Session finished.
** rendered 5972 frames in 33.049 secs, 180.701 fps
audio0 pad 64 0 (64)

Decoder libdav1d does not support device type vaapi.
HW device init failed, using SW decode.
file:/Videoklipp/QSV/hdv09-04_cin_av1_qsv_8b420.mp4
  err: Operation not permitted
Decoder libdav1d does not support device type vaapi.
HW device init failed, using SW decode.
file:/Videoklipp/QSV/hdv09-04_cin_av1_qsv_8b420.mp4
  err: Operation not permitted
Total excess of backups: -50 
Session time: 0:22:43
Cpu time: user: 0:01:24.375 sys: 0:00:14.084
unjoined tids / owner 3
  00007f88517ff6c0 / 00007f88d16b96c0 12RenderEngine
  00007f886b7fe6c0 / 00007f88d16b96c0 12RenderEngine
  00007f88797fa6c0 / 00007f88d16b96c0 12RenderEngine