ProRes conversion

[timsky]

I have some footage shot in H.264 which I want to convert to ProRes. Would ProRes 422HQ give better visual quality than ProRes 422, given that the original footage is in H.264?

[poisondeathray]

I have some footage shot in H.264 which I want to convert to ProRes. Would ProRes 422HQ give better visual quality than ProRes 422, given that the original footage is in H.264?

Yes;

or Prores 422 HQ would have less quality loss than Prores 422 STD . It's a "glass half empty or glass half full" sort of thing

The "negative" is HQ would take more bitrate and storage space

If the src footage is noisy, there are some cases where subjectively HQ might appear worse to some people, because it preserves more noise, and STD, in effect, denoises it because it retains less signal

[timsky]

Thanks for the reply. The footage isn't visibly noisy. But isn't H.264 severely degraded in quality anyway? So any further slight degredation due to ProRes 422 would not be noticeable?

[poisondeathray]

But isn't H.264 severely degraded in quality anyway?

Not necessarily - it depends on the source, bitrate, recording quality etc...

"h.264" is large standard with many different profiles

Yes, the garden variety cheap h264 recordings which are low bitrate can be severely degraded; but some cameras shoot h.264 profiles at 444 , intra, 12bit high bitrate (960Mb/s) etc... ie. Higher quality than Prores 422 HQ.

No current camera shoots this profile - but h264 can actually be lossless too...

So any further slight degredation due to ProRes 422 would not be noticeable?

Depends on the recording, the situation, and the person . Quality loss for Prores HQ is definitely noticable to some people. That's why there is Prores 444 XQ

Try some short tests to see if it's "good enough" for you for that recording

"quality" means different things to different people. eg. Some people think Youtube qualtiy is great. Others think it's garbage


Or another option is don't convert. Why convert to ProRes in 2022 ?

[timsky]

Thanks again for the reply. I know I'm being a bit obsessive about this, but I like to fully understand what I'm dealing with so I can make informed judgements in the future. My H.264 was shot on a "prosumer" camera Canon HFG 25 in 4.2.0 HD 8-bits, so it's not pro quality. I exported it from Premiere Pro in uncompressed which is obviously enormous files, so want to convert it to ProRes to make it smaller, but preserving the full H.264 quality, which is much better than H.264 converted to H.264 again (I can see that with my own eyes, the definition is far worse.)

[poisondeathray]

Thanks again for the reply. I know I'm being a bit obsessive about this, but I like to fully understand what I'm dealing with so I can make informed judgements in the future. My H.264 was shot on a "prosumer" camera Canon HFG 25 in 4.2.0 HD 8-bits, so it's not pro quality. I exported it from Premiere Pro in uncompressed which is obviously enormous files, so want to convert it to ProRes to make it smaller, but preserving the full H.264 quality, which is much better than H.264 converted to H.264 again (I can see that with my own eyes, the definition is far worse.)

There are different categories of "h.264" encoders as well.

Also, you have to compare at equivalent bitrates for a valid comparison.

But yes, everyone complains about Premiere's AVC encoder (Mainconcept) - it's just not very good. Very soft and substantial loss of details. Just look on any video forum, including Adobe. Many comparisons and tests

People tend to use x264 using voukoder plugin these days. In the old days people would frameserve out, or use a lossless intermediate, and use something like handbrake or x264cli directly



Now if you used comparable specs to ProRes (10bit 422, Intra encoding); Then AVC-Intra (I-frame) using a good AVC encoder (such as x264) at the same bitrate, AVC is about 10-20% better in quality than ProRes HQ, but decodes slower than ProRes. And if you're on a Mac, ProRes is much much faster.

If you want to save more space, use long GOP 10bit AVC (using a good AVC encoder) is about 20-40% better than Prores HQ in terms of PSNR or SSIM measurements.

If you wanted to save even more space, and just use 8bit 4:2:0 long GOP similar to your source material, you could reduce the bitrate even more to get similar quality as ProRes HQ (if you used a good AVC encoder such as x264)

[timsky]

WOW what a lot of information. Maybe this explains why my video edited in Pre Pro looks so much worse than the original when exported as H.264? What about H.265? Is Pre Pro bad at exporting that as well? I will have to use H.265 in future anyway because all my future films will be in UHD 50p. Can you get a high-quality H.265 plug-in for Pre Pro? Also does Pre Pro degrade the quality of ProRes when exporting it, or is that not possible?

[poisondeathray]

Maybe this explains why my video edited in Pre Pro looks so much worse than the original when exported as H.264?

If you exported uncompressed earlier, and checked that is was ok - that rules out other possible issues with sequence settings, export settings etc... so yes that suggests the fault was Premiere's h.264 encoder assuming you used a decent bitrate. If you use very high bitrates PP's AVC export can look ok, but it's sort of a waste when you can use another encoder, get smaller filesizes AND higher quality

What about H.265? Is Pre Pro bad at exporting that as well?

It's not that great either, but the difference isn't as large when compared to Premiere's HEVC encoder vs. x265 for h.265. There is a more significant difference when using PP h.264 vs. x264

I will have to use H.265 in future anyway because all my future films will be in UHD 50p. Can you get a high-quality H.265 plug-in for Pre Pro?

voukoder can too - libx265

Also does Pre Pro degrade the quality of ProRes when exporting it, or is that not possible?

ProRes is a lossy format. It's considered "visually lossless" or high quality, but there is some deterioration everytime you use a lossy format . But prores HQ is probably "good enough" for 99% of general use cases, even with 2-3 generations

If the input source was ProRes, and you only did cuts type editing, then it can be lossless Prores export (basically stream cutting and pasting) . This is known as "smart rendering". If you use any filters/grading etc... it will force a re-encode




Here is some test data for UHD 10bit422 src

Basically, ProRes HQ was 1.66x larger, but 4-5db lower in quality than x264 intra @CRF1 . You could probably cut it by more than 1/2 size of prores and still have higher quality than ProRes using long GOP mode, if the source did not have a lot of motion or noise (using temporal compression for Long GOP).

It's source dependent, but x264 will practically always result in higher quality than prores at similar bitrates, even in Intra mode. But the decoding speed is much slower even when tuning it for fast decoding settings. Another way of saying this is x264 a more advanced compressed encoder than Prores, and takes more resources to decompress/decode even when using Intra only mode. Prores is simpler

https://forum.doom9.org/showthread.php?p=1884556#post1884556

ProresHQ (ffmpeg)
591Mb/s
psnr_avg:68.73 psnr_y:67.46 psnr_u:69.74 psnr_v:71.49

x264cli --crf1 --keyint 1
356Mb/s
psnr_avg:73.20 psnr_y:70.83 psnr_u:78.08 psnr_v:79.68

x264cli --qp1 --keyint 1
512Mb/s
psnr_avg:82.08 psnr_y:79.72 psnr_u:86.44 psnr_v:89.33

[timsky]

I tried doing a conversion from ProRes 422HQ HD 25p to H.265 12-bit using Handbrake set to Encoder Level 5.2, 2-pass Encoding, Avg bitrate, Slow, and it looks good. And the file size is only 64.5 MB while the previous H.264 version exported from Pre Pro was 566MB! Does this workflow and these settings seem appropriate to you?

[poisondeathray]

Thank you very much for all that help. ProRes doesn't seem so wonderful to me now.

Prores STD/HQ is generally not used as finishing / end delivery format. It's used more upstream sometimes for acquisition, sometimes for intermediates because less compressed to make it easier for editing. It's I-frame only (intra) so it offers zero temporal compression, thus larger filesizes (AVC is newer, more advanced so even in I-frame mode it can offer higher compression and quality...assuming you're using a decent implementation of AVC encoder)

HW decoding of some types of AVC and HEVC formats makes them easier to edit, if your editor and HW support it. Software decoding of UHD HEVC is very slow and sluggish to edit - very high latency and palpable pauses. But Prores software decoding (even on a PC) makes UHD smoother and easier/faster to edit. On newer macs, there is HW acceleration of Prores and UHD "feels" like SD DV to edit - it's instantaneous and snappy

AVC has many different profiles (or "flavours"), so it has the ability to cover almost every type of situation, from acquisition, intermediates, high compression , low compression, end delivery, different subsampling and bitdepths, intra and long gop - it's very versatile

[timsky]

I tried doing a conversion from ProRes 422HQ HD 25p to H.265 12-bit using Handbrake set to Encoder Level 5.2, 2-pass Encoding, Avg bitrate, Slow, and it looks good. And the file size is only 64.5 MB while the previous H.264 version exported from Pre Pro was 566MB! Does this workflow and these settings seem appropriate to you?

[poisondeathray]

I tried doing a conversion from ProRes 422HQ HD 25p to H.265 12-bit using Handbrake set to Encoder Level 5.2, 2-pass Encoding, Avg bitrate, Slow, and it looks good. And the file size is only 64.5 MB while the previous H.264 version exported from Pre Pro was 566MB! Does this workflow and these settings seem appropriate to you?

Hard to say, you'd have to look at the input(s) and output(s) to compare. I doubt the quality would be similar, even if PP h.264 was 566MB vs. 64.5 MB for x265 . h.265 not that much better. Double check to see if you have same audio, or missing audio for one.

What is the target or situation end goal? How is it going to be played or used ? One potential issue is h.265 12bit is not supported by common hardware (or any hardware, it's software decoded). But 10bit 4:2:0 Main10 profile is supported by many recent generation of devices like smart TV's , tablets, phones etc... Even some software like NLE's have poor support for 12bit h.265

[poisondeathray]

BTW, one issue is HB still does not have a true 10bit or 12bit pipeline . It's only 8bit. It's one of the most requested improvements for HB, but still hasn't gone through.

It's less important since your actual source as 8bit, but if you had true 10bit src, when you feed HB 10bit input, it has an 8bit step, so there is banding . Also it dithers , so the filesize is larger instead a proper clean conversion (in that thread it's 10x larger, but only because it was a clean ramp test signal)

https://forum.videohelp.com/threads/397681-Xmedia-recode-true-10bit-encoding-and-hdr


You can use other GUI's such as staxrip, hybrid which have proper pipeline, or if you're comfortable with cli, you can use x265 directly

[timsky]

Audio and picture seem the same. Why is the H.265 file size so much smaller than H.264? The data you sent said H.265 is 1-3 times smaller.
At present I show videos to friends etc on their PCs, and some of my videos are on YouTube. I haven't tried sending them to phones.
12-bit H.265 was the maximum available in Handbrake. Would 10-bit be noticeably worse? What bit-rate is normal H.264 exported from Pre Pro?

I posted this before reading your later post. So what bit-rate would you recommend for my 8-bit videos? And which of staxrip or x265 is best?

[timsky]

So what bit-rate would you recommend for my 8-bit videos? And which of staxrip or x265 is best? Is HB not so good?

[poisondeathray]

Why is the H.265 file size so much smaller than H.264?

Filesize is dependent on bitrate . Filesize = bitrate * running time

So you're using different bitrates

The thing you're missing is some measure of "quality", even if it's your eyes . x265 is not 10x better than PP AVC.

12-bit H.265 was the maximum available in Handbrake. Would 10-bit be noticeably worse?

No

What bit-rate is normal H.264 exported from Pre Pro?

The encoder bit depth is 8bit, but the bit rate varies according to the video or what you enter. Harder to compress material (noise, lots of motion, lots of details, high contrast) requires higher bitrate to achieve a certain level of "quality".

So what bit-rate would you recommend for my 8-bit videos?

Depends on the resolution, content complexity. People geneally use "quality" based encoding, and the filesize varies according to the source characteristics. A still frame "movie" would take very little bitrate, a few kb/s to look good. An action movie might take 40Mb/s to look good. "quality" based encoding such as "CRF" when using x264 or x265 automatically determines that for you. Lower CRF values yield higher quality, higher bitrates

But if you arbitrarily picked some values , and don't have much experience with encoding or a specific encoder - it might be too much or too little for that specific source

And which of staxrip or x265 is best?

staxrip is a GUI that has several encoders, including x265

x265 is an open source encoder implementation of HEVC. Almost all open source GUI's use x265 library for HEVC software encoding , including handbrake. There is also HW HEVC encoding , such as NVEnc (Nvidia), Quicksync (Intel) . In general, software encoder is slower but yields better quality. NVEnc HEVC (turing cards or newer) is not that much worse than x265, however, and the speed is 10-20x faster

[timsky]

Is "Quality based encoding" a selectable option in staxrip? I want the best quality. I don't care about speed.

[poisondeathray]

Is "Quality based encoding" a selectable option in staxrip? I want the best quality. I don't care about speed.

Yes, staxrip should have it , either "CRF" or "quality" based . I don't have it installed on this computer

You probably don't want absolute "best". "Best" quality is lossless encoding. Filesizes are enormous, but ~1/2 the size of uncompressed data. PSNR would be "infinity"

You probably want some trade off, like decent filesizes, but high quality. For 10bit HEVC, using x265, people generally use in the range ~CRF 16-26 for general use . If you want higher quality, larger filesizes use a lower CRF like 10-12

2pass encoding is generally only used when you have bitrate restrictions, like fixed capacity such as optical disc (UHD BD) . Or you have a specific filesize or limit you need to hit for some reason

And you should care about speed to some extent. Some of the settings are absurd, like 10-20x slower for 0.001% bitrate savings. Maybe a few days to encode a movie. There is a reason why the slowest preset is called "placebo". A good place to start is using the "slow" preset for general use, and I wouldn't go slower than "very slow" preset for anything else. There are severe diminishing returns once you start going into the slower settings

[timsky]

I tried downloading staxrip but it said I don't have an app associated with it, whatever that means.

[timsky]

It's 5.10 am in my part of the world so I'm going to bed now.

[ricardouk]

Here's my "quick and dirty" Prores converter script, unzip the folder to any location, drag and drop your file and follow the instructions, be warned im a newbie when doing "scripts", hope it helps