Page 1 of 1

Not doing 2 pass encoding and subtitle issues

Posted: Sun Apr 11, 2021 1:28 am
by oobedoob_benubi
Description of problem or question:
Been using Handbrake for awhile. Noticed recently that it's only doing 2 pass encoding when it feels like it. I'm not sure if it's connected, but it appears that if I uncheck the "Forced Only" in the Subtitles tab it seems like it will only do one pass. I've checked the settings in the Video tab and 2-Pass Encoding is checked, although I'm unable to check or uncheck it as it's greyed out, but there is a check in the box. I've tried messing around with settings and nothing appears to make the box selectable.

I've also never had a successful encode with using the Foreign Audio Scan option in the Subtitles tab. I always have to uncheck the Forced Only and then test each subtitle track to see which one is the correct track to use. Not sure if I'm using this setting incorrectly or if there's something wrong with the settings, but I've just never gotten this to work it's always been a manual process for me (which gets a bit tedious when I have several seasons of a show that needs to have some or full subtitles burned into the encode).

Steps to reproduce the problem (If Applicable):
For the 2-pass encode issue it looks like it may be when subtitles are manually applied it only does one pass, but I'm not sure if that's true.

Subtitle issue, never been successful with getting it to work

HandBrake version (e.g., 1.0.0):

1.3.3


Operating system and version (e.g., Ubuntu 16.04 LTS, macOS 10.13 High Sierra, Windows 10 Creators Update):

Windows 10 2004 Update


HandBrake Activity Log ***required*** (see How-to get an activity log)

I've included two episode logs. The first one is an example for the 2-pass issue the second is an example for the subtitle issue.
https://pastebin.com/0DyGrY0j

Re: Not doing 2 pass encoding and subtitle issues

Posted: Sun Apr 11, 2021 10:15 am
by s55
Couple of quick points.
1. Forced is a type of subtitle. If your subtitles do not include forced subtitles, nothing will appear. This is correct behaviour.
2. Foreign Audio "Scan" requires an additional pass. This is NOT 2-pass encoding.
3. 2-Pass encoding can be activated on the video tab if the video encoder supports it. Noting that there may be 3 passes for Foreign audio scan if that's also enabled.

Cheers

Re: Not doing 2 pass encoding and subtitle issues

Posted: Mon Apr 12, 2021 4:51 pm
by oobedoob_benubi
s55 wrote: Sun Apr 11, 2021 10:15 am 3. 2-Pass encoding can be activated on the video tab if the video encoder supports it. Noting that there may be 3 passes for Foreign audio scan if that's also enabled.
Could this be explained a bit more? I usually put anywhere from 80 to 100+ files in the queue to encode overnight, but I'll sometime watch it encode a few before leaving it for the night. I can see some files will encode with 2 passes and then the next file will encode with only one pass all using the same presets and settings. The only difference may be subtitles and/or audio settings, but I usually never touch the video or filter settings.

Re: Not doing 2 pass encoding and subtitle issues

Posted: Mon Apr 12, 2021 5:02 pm
by s55
If you don't have 2 pass enabled on the video tab, then you are always doing 1-pass video and maybe 1 pass scanning for subtitles.
The subtitle scan pass only looks for subtitles where actors are speaking a foreign language. It does not alter video quality in anyway.


Having looked at your log file, you are using Quality based encoding, not average bit-rate based encoding:
[20:57:26] + quality: 22.00 (RF)

With quality based encoding, there is no "2pass" mode. It's always 1 pass for the video encode.
Only average bit-rate supports 2-pass as you need to scan the file first to determine bit-rate distribution for an optimal file.

Quality based encoding essentially does this in real-time in 1 pass and generally considered better overall.

Re: Not doing 2 pass encoding and subtitle issues

Posted: Mon Apr 12, 2021 6:22 pm
by oobedoob_benubi
Thanks for the clarification. Still getting used to encoding files from MakeMKV rather than ripping directly off disc like back in the medieval days :)