2024-04-26, 09:55 PM
Hey ! I'm trying to use correctly the transcoder, as every film I host has different resolutions, codecs, bitrates, color range, etc
But I'm stuck on something, it's the maximum transcoding quality.
To put it simple, no matter how I try to tune the transcode quality, it will be capped at around 10-11 Mbps (or around 1.5x the original bitrate), which is not enough, I can see artifacts and blocking. Not so much that I can't use the result at all, but still visible.
Let's take an example on this film
Viewer dimensions:
1872x1004
Video resolution :
3840x2076
Transcoding info :
Video codec :
H264
Codec audio :
AAC (direct)
Bitrate:
11.6 Mbps
Transcode fps :
232 fps
Why is it transcoding :
The video's range type is not supported
Original file info
Container :
mkv
Size :
5.4 GiB
Bitrate :
8.1 Mbps
Video Codec :
HEVC Main 10
Video Bitrate :
6.6 Mbps
Video range type:
HDR10
Codec audio :
AAC LC
Bitrate audio :
768 kbps
I'm viewing with the 4k - 120Mbps setting
I'm on localhost, so there is no connection bottleneck
I'm aware that the original file is not top-notch quality, BUT, the encoding is good and when directly viewing it with VLC, I don't see any blocking or artifacts. As I'm in the best conditions possibles (localhost, only user, hardware acceleration), I would aim to have a similar transcoded quality perception, even at the price of a big bitrate. (I mean, the parameter says 120Mbps, right ?)
So here, the transcoding happens because my screen can't display HDR, which is the case, so all good.
But as you can see, the transcoded bitrate is low, (and so is the perceived quality).
I have hardware acceleration enabled (RTX 2080 Super), and I don't know what could be causing this problem
I tried to change the encoding CRF to absurd values just for testing purposes, I see 0 differences, not in the slightest, I don't know if these values or used at all (or if I misconfigured something)
I didn't try to change the encoding preset as in my understanding of things it affects quality for a given bitrate (or at least it changes the speed or encoding more than the bitrate itself). I will still try as I have some performance headroom, but it wouldn't be a real solution
So I'm here asking for help
If this is expected behavior, can you explain to me why ?
And if not, how to correct this ? Thanks a lot !
But I'm stuck on something, it's the maximum transcoding quality.
To put it simple, no matter how I try to tune the transcode quality, it will be capped at around 10-11 Mbps (or around 1.5x the original bitrate), which is not enough, I can see artifacts and blocking. Not so much that I can't use the result at all, but still visible.
Let's take an example on this film
Viewer dimensions:
1872x1004
Video resolution :
3840x2076
Transcoding info :
Video codec :
H264
Codec audio :
AAC (direct)
Bitrate:
11.6 Mbps
Transcode fps :
232 fps
Why is it transcoding :
The video's range type is not supported
Original file info
Container :
mkv
Size :
5.4 GiB
Bitrate :
8.1 Mbps
Video Codec :
HEVC Main 10
Video Bitrate :
6.6 Mbps
Video range type:
HDR10
Codec audio :
AAC LC
Bitrate audio :
768 kbps
I'm viewing with the 4k - 120Mbps setting
I'm on localhost, so there is no connection bottleneck
I'm aware that the original file is not top-notch quality, BUT, the encoding is good and when directly viewing it with VLC, I don't see any blocking or artifacts. As I'm in the best conditions possibles (localhost, only user, hardware acceleration), I would aim to have a similar transcoded quality perception, even at the price of a big bitrate. (I mean, the parameter says 120Mbps, right ?)
So here, the transcoding happens because my screen can't display HDR, which is the case, so all good.
But as you can see, the transcoded bitrate is low, (and so is the perceived quality).
I have hardware acceleration enabled (RTX 2080 Super), and I don't know what could be causing this problem
I tried to change the encoding CRF to absurd values just for testing purposes, I see 0 differences, not in the slightest, I don't know if these values or used at all (or if I misconfigured something)
I didn't try to change the encoding preset as in my understanding of things it affects quality for a given bitrate (or at least it changes the speed or encoding more than the bitrate itself). I will still try as I have some performance headroom, but it wouldn't be a real solution
So I'm here asking for help
If this is expected behavior, can you explain to me why ?
And if not, how to correct this ? Thanks a lot !