Too low compression / banding

Topaz Video AI Bugs and Issues
1

Hi.

I’m testing Topaz Video AI, but it seems there is a big problem with too low compression.

For several days I processed various files, but only on deliberately underexposed shots (dark silhouettes on a light background) I noticed huge banding (much larger than in the original files).

The original files from the camera have a bitrate of 100mp/s. Even though Topaz is set to a bitrate of, for example, 180 (larger than original files), the final files get a smaller size and a much lower bitrate than the original files straight from the camera.

Of course, I’m talking about files that were “only stabilized” - not those scaled from, for example, Full HD to 4K.

Below is a compression comparison - I intentionally brightened this photo so you can see the problem better.

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3

Thanks for sharing this :slight_smile:

More than likely we will need to train a model specifically for these types of files. In the meantime, can you please share the following;

  1. Input file
  2. Exact reproduction steps
  3. Exported file

You can securely submit your files(s) to our Dropbox using the link below. Please be sure to send me a note to let me know you sent something.

Submit File to Dropbox

4

Porównanie
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Thank you very much for your answer. I will describe everything in points to describe the problem as understandable as possible. Forgive my poor english :slight_smile:

I sent you a drop box file called “2023-03-28 - Topaz Video AI - Compression Banding” - its a file straight from the camera.

I wanted to use Topaz Video to stabilize files before editing. I turned off all “enhancements” and set the parameters to zero. The source file is 3840x2160. The camera is a Sony a6300/A7III with a maximum bitrate of 100Mbps. After stabilization in Topaz, of course, I get a file with a lower resolution (“auto-crop” function).

I tested this problem on different codecs, different files.

  1. As an experiment, I ran a file through Topaz with everything turned OFF (even stabilization was turned off - no enhancer, no resolution changes, no framerate, etc).

a) Prores 422 HQ - the problem appeared and the color was changed.

b) MP4 birate 180 (higher than the file straight from the camera) - the problem also appeared, but finally the rendered file bitrate from Topaz Video AI was lower than the file straight from the camera - about 80Mb/s

  1. The problem is very visible in out-of-focus shots (for example, when I move the camera dolly out of the wall). However, compression also appears on faces, in dark parts of clothes (underarms, for example), in the sky, walls, cars - literally all “smooth surfaces” so to speak - just like overly compressed jpg files. Of course, the problem is less visible on textured items, but still visible when zoomed in. I hope you know what I mean - in the files straight from the camera you can see a slight “noise”. In Video AI files we see smooth, compressed pixels.

  1. It is least noticeable in shots with a lot of detail, where there are no uniform surfaces and no blurred background, etc.

  2. When saving to Prores, we get gigantic file sizes that are difficult to compress. I also tested Prores and files in different formats, but it added a lot of processes to my workflow.

It seems to me that that Topaz sets by itself “the right birate”. Despite the target bitrate (180 Mb/s), the files weigh less than the “negative” straight from the camera.

In other programs, for example in Adobe Media Encoder, we can set the CBR (Constant) bitrate - maybe this solution would help if there was such a function in Topaz Video AI?

Of course, I realize that my cameras are not in the highest league, but you can clearly see the banding and compression in the Topaz Video AI files, which should have a higher bitrate than the files straight from the camera (we should "artificially increase the size of the files to prevent damaging compression).

Maybe “forcing” the program to keep the bitrate constant throughout the file would help? Unfortunately, this also appears in Prores files, despite the fact that they have a gigantic bitrate and weight.

And here’s another example. The left shot is a file straight from the cameras, and the right shot is from Topaz AI.

For the Topaz shot, UHD scaling (after auto-crop stabilization) was enabled.

I brightened this shot so that you can see the difference in the browser.

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6

Thank you! I am having our team look into this.

1 Like
7

Thank you very much <3

9

Good morning!

Our development team was able to identify the problem. It will take time to dig into it more. For a quick work around, I would suggest to export to PNG or TIFF sequence.

1 Like
10

Thank You very much! Such a great news! I’ve tested the PNG export and the problem seems to be gone - I’ll test it very thoroughly some day. I can’t wait until the problem disappears when exporting to MP4 files, because rendering PNG files for thousands of video files would be quite… problematic :slight_smile: I love you guys! I’m keeping my fingers crossed very hard!

1 Like
11

Awww! I am glad to hear that :slight_smile:

I will post here once the issue is fully resolved!

13

Was this ever resolved? Thank you!

14

Same here, i do get banding problems due to insufficient bitrate… is there a solution yet other than exporting as image sequence?

16

Hello,

Could I take a look at the app’s log files to see what bitrate control settings are being applied by Video AI?

To gather logs, please select Help > Logging and make sure that there is a check mark next to File Logging. Next, recreate the issue and then return to the Help menu and select > Get Logs for Support

You can upload the “logsForSupport.zip” file here:

Submit to Dropbox

17

Hi.

In the current version of the program (Topaz AI 5 - 5.01) I can finally see a huge improvement in quality <3 The banding problem has probably disappeared - at least in the following test, the first one I have just performed. Thank you very much - I will try to post more examples to finally confirm whether the problem has been solved.

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Thank you very much, because stabilizing the source camera files with your program before editing is a real game changer.

However, I see that the program sometimes still compresses files too much. Despite selecting the “constant bitrate 180Mb/s” option, it receives files with a bitrate of e.g. “+/-65Mb/s” or even “+/-40Mb/s”, while the raw files from the camera had a bitrate around 100Mb/s.

I will add that the problem of “too low bitrate” appears mainly in files with a shallow depth of field (e.g. blurred background).

Jn shots without a blurred background (for example, wide shots with a lot going on), the bitrate of files from Topaz Video is about 100 Mb/s - more or less the same as the source files from the camera/camera.

It would be nice if topaz kept the minimum value (even artificially increasing the file weight) - so that various “artifacts” did not appear in the further stages of editing, color grading e.t.c. and processing video files.