Should AV1 size be bigger than HEVC?

I’ve been using MP4 HEVC with success. I wanted to see if AV1 would be any better, so I converted an HEVC file to AV1. What happened was a file 224mb HEVC to 330mb AV1, an almost 50% increase! I’m on Win11, MCEBuddy 2.6.3. I used the standard MCEBuddy profiles. My AV1 file was converted with an Nvidia RTX 4070 Ti with the current Nvidia game drivers. I’ll try to do the MCEBuddy log.

Any comments?

Extraordinary - s01e07 - The Merry Monarch.mp4-Convert to MP4-2024-06-06T08-02-04.log (29.9 KB)

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Your logs arent set to debug so there’s really nothing in them to analyze. You can change them in Settings → system settings → logs → debug

debug log →
Extraordinary - s01e07 - The Merry Monarch.mp4-Convert to MP4-2024-06-06T16-03-54.log (778.5 KB)

I see what’s going on. Your starting bitrate was 1Mbps and when your Nvidia GPU converted it, it’s using a slightly higher quality so the final bitrate is 1.6Mbps which is why your resulting file is larger (this happens due to a proprietary nature of the Nvenc implementation v/s the software implementation and so the mappings between the two don’t always match).

Try this, on the Conversion task page, reduce the Quality slider to -50% and it should reduce your bitrate by approx half (or more if you want to go smaller) and you shouldn’t experience any significant quality loss but it should reduce your file size.

Post your conversion log back here so we can see what’s going on.

Win11 had the property Total Bitrate, so this is easy for me to see.

-50% Quality on AV1+Nvidia gave me a 0.5Mbps and 109MB file. The video was a bit muddy.

-25% Quality on AV1+Nvidia gave me a 0.9 Mbps and 184MB file. The video was as clean as 0 Quality.

(-50%)Extraordinary - s01e07 - The Merry Monarch.mp4-Convert to MP4-2024-06-07T10-33-41.log (778.7 KB)
(-25%)Extraordinary - s01e07 - The Merry Monarch.mp4-Convert to MP4-2024-06-07T10-40-52.log (778.3 KB)

My media center PC has a Ryzen 5600G and no extra GPU. My PlayOnHome MP4’s had 4.6Mbps. I use MCEBuddy to kill commercials and convert to HEVC. I’m happy with the file size. The videos seem OK. To convert to AV1, I need to make sure my other devices can do AV1, won’t suck my battery, and get smaller files and still get good videos. I’m not there, yet.

And no, I haven’t converted my PlayOnHome MP4’s directly to AV1. Would this make a difference?

Goose: Does that mean, to do AV1, I will have to tune the MCEBuddy Quality value per GPU device? Your MCEBuddy MP4 HEVC profile was so easy with 0 Quality.

Thanks for the logs. AV1 is a still a new profile and needs some tweaking that we’re working on. You don’t need to do that each time. Here’s a quick and permanent fix.

Open profiles.conf and under the MP4 AV1 profile change the -q 32 to -q 39 in the ffmpeg-video and handbrake-video lines.

Now it should work as expected with 0% quality.

profiles.conf →
[MP4 HEVC] BEFORE
ffmpeg-video=-ss 0 -tag:v hvc1 -vf yadif=0:-1:1,hqdn3d -vcodec libx265 -preset medium -crf 26 -map 0:v -sn
handbrake-video=–start-at duration:0 -e x265 --encoder-preset medium -q 26

[MP4 HEVC] AFTER
ffmpeg-video=-ss 0 -tag:v hvc1 -vf yadif=0:-1:1,hqdn3d -vcodec libx265 -preset medium -crf 26 -map 0:v -sn -q 39
handbrake-video=–start-at duration:0 -e x265 --encoder-preset medium -q 39

Is my BEFORE and AFTER correct?
Will it be correct for AMD encoding?
What happens where I install MCEBuddy 2.6.next?
And so I don’t pester you, how do I know to do -q 39?

You changed the wrong profile. The AV1 profile, not the HEVC

[MP4 AV1]
ffmpeg-video=-ss 0 -vf yadif=0:-1:1,hqdn3d -vcodec libsvtav1 -preset 6 -crf 39 -map 0:v -sn
handbrake-video=–start-at duration:0 -e svt_av1 --encoder-preset 6 -q 39

Is this correct under ffmpeg-video: -crf 39, not -q 39

Yes, that’s correct, my typo earlier.
-crf in ffmpeg and -q in handbrake