[FFmpeg-user] Quality Reduced when Burning Subtitles

[Veronica & Stephen McGuckin]

Hello Moritz,

Thank you for your follow up. I have attached a word document which provides the console output. I have also attached a screen shot showing the file data as reported by Mediainfo. It shows the file size as 143 MB and the bit rate as 279 b/s. As you can see from the output I didn't get a syntax error (or at least I think I didn't). By the way how can I tell from the output which CRF actually takes effect?

Once again thanks for any advice you can provide.

Regards

Stephen

-----Original Message-----
From: ffmpeg-user <ffmpeg-user-bounces at ffmpeg.org> On Behalf Of Moritz Barsnick
Sent: 05 September 2021 15:33
To: FFmpeg user discussions <ffmpeg-user at ffmpeg.org>
Subject: Re: [FFmpeg-user] Quality Reduced when Burning Subtitles
143
On Sun, Sep 05, 2021 at 13:43:22 +0000, Veronica & Stephen McGuckin wrote:
> ffmpeg -i c:\video\input.mkv -filter_complex "[0:v][0:s]overlay[v]" 
> -c:v libx265 -pix_fmt yuv420p10le -profile:v high  -x265-params 
> "-crf=10 -film -hdr10+=1 -preset slow" -map "[v]" -map 0:a:0 -c:a copy 
> c:\video\output.mkv

Please show us the complete, uncut console output of the command. It would e.g. show which CRF actually takes effect.

I would actually expect an error from this option:
  -x265-params "-crf=10 -film -hdr10+=1 -preset slow"
That's not the correct syntax for x265-params.

https://ffmpeg.org/ffmpeg-codecs.html#Options-32
Quote:

    Set x265 options using a list of key=value couples separated by ":". See x265 --help for a list of options.
    For example to specify libx265 encoding options with ‘-x265-params’:
      ffmpeg -i input -c:v libx265 -x265-params crf=26:psy-rd=1 output.mp4

Perhaps you meant to use those "x265-params" as actual ffmpeg options.

> When the conversion is complete the output file is 143 mb with a bit rate of 279 b/s.

I honestly doubt the 279 b/s. That would mean your video is 4299537 seconds long (if you mean 143 MB size - 537442 seconds if you mean 143 Mb). Did you mean 279 kbit/s?

Cheers,
Moritz
_______________________________________________
ffmpeg-user mailing list
ffmpeg-user at ffmpeg.org
https://ffmpeg.org/mailman/listinfo/ffmpeg-user

To unsubscribe, visit link above, or email ffmpeg-user-request at ffmpeg.org with subject "unsubscribe".
-------------- next part --------------
A non-text attachment was scrubbed...
Name: ffmpeg Command Output.docx
Type: application/vnd.openxmlformats-officedocument.wordprocessingml.document
Size: 18047 bytes
Desc: ffmpeg Command Output.docx
URL: <https://ffmpeg.org/pipermail/ffmpeg-user/attachments/20210906/ef13f8dc/attachment.docx>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: Mediainfo Parasitev1.png
Type: image/png
Size: 278535 bytes
Desc: Mediainfo Parasitev1.png
URL: <https://ffmpeg.org/pipermail/ffmpeg-user/attachments/20210906/ef13f8dc/attachment.png>