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Urgent! - Transcoding H.264 to ProRes - Question

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Hi folks, I'm just about to begin transcoding (AME) a large amount to h.264 (5DM2) files to ProRes.
I've done a few tests and the output file has a thin strip of black at the bottom of the frame almost as if the file is somehow not 1920x1080. This black is also visible in the source file. The thing is that I've never noticed this 'thin strip of back at the bottom before until I upgraded to Mojave and CC2019.
Can anyone open a h.264 file and tell me if there is a thin black strip at the bottom? Mojave? PPro 2019CC? Does anyone know the fix? 

And actually, I've just transcoded a huge amount of mpeg2 material (XDCAM) to ProRes and somehow the transcoded frame has more in it, just a tiny amount more (wider) but it's not there in the original file. But this material does not have the thin black strip at the bottom. Anyone?

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I had a similar issue with CC2019, the file were Cineform though and the tiny strip was white and on the right side of the frame (vertical line on the edge). I haven't noticed anything in h.264.

I messed with Premiere for one hour trying to figure out what was going on but I couldn't find the source of the problem nor a quick fix so I decided to apply a tiny bit of crop on the entire timeline (something like 100.1) and the line was not visible anymore. Not ideal but it fixed the problem rapidly until the geniuses at adobe can fix their beta software in 6 months. If anything, It reminded me why I usually never jump on the latest version. I'm back to CC2017 now... #adobe

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43 minutes ago, OliKMIA said:

I had a similar issue with CC2019, the file were Cineform though and the tiny strip was white and on the right side of the frame (vertical line on the edge). I haven't noticed anything in h.264.

I messed with Premiere for one hour trying to figure out what was going on but I couldn't find the source of the problem nor a quick fix so I decided to apply a tiny bit of crop on the entire timeline (something like 100.1) and the line was not visible anymore. Not ideal but it fixed the problem rapidly until the geniuses at adobe can fix their beta software in 6 months. If anything, It reminded me why I usually never jump on the latest version. I'm back to CC2017 now... #adobe

Thanks again for the support OliKMIA! Good to have your thoughts. I thought of the crop as well... ugh. I may have to look towards CC2017... though several weeks of the project has been built in CC2019.

 

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2 minutes ago, KnightsFan said:

Have you looked at the file in other programs? Can you confirm whether it's exclusively a Premiere problem, or is the problem with the files themselves?

Thanks for jumping in KnightsFan.

The original material in PPro has the black stripe at the bottom but not when I open it in Quicktime.
The same material transcoded by FCP7 Compressor into ProRes and placed on PPro timeline has no black stripe.
The original file transcoded to to ProRes by AME and placed on a PPro timeline next to the others has the black stripe.

Adobe at their best again?

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I think I got it sorted.
In AME, I created an encoding Preset where I didn't select the "Match Source" tick box and instead set the Height & Width dimensions manually to 1920x1080.
So far so good.

Thanks again for jumping in guys... I'm way out on the bright side of nowhere here... years at a time. This place is a huge resource is a godsend to folks like me :)
Onward!

*Edit!!!
Woops! Spoke too soon... I converted the wrong file. The black stripe is still there.

The Headless Leader at Adobe strikes again... others having the same issue:
https://forums.adobe.com/thread/2555018

This is a bug. Disable the "Enable hardware accelerated decoding" option in Preferences > Import. Restart After Effects, then purge the cache via Edit > Purge > All Memory & Disk Cache.

It appears that After Effects 16.0 (and Premiere Pro 13.0) are mis-sizing Canon 5D H.264 .mov footage when hardware-accelerated H.264 decoding is enabled on Mac. The bottom 128 pixels of the footage are black, and the footage is vertically scaled so that it fits within the cropped dimensions. In more concrete terms: a 1920x1080 frame renders vertically scaled (squished) to 1920x952, with the last 128 rows filled with black.

I do not reproduce this problem with any other H.264 footage, just the Canon 5D samples that I have. The same samples do not reproduce the problem in After Effects on Windows 10. Premiere Pro also appears to be affected by the problem as well (same technology; in Premiere Pro the hardware acceleration option is in Preferences > Media.) Note that the hardware acceleration option is only available on macOS 10.13 and later.

The problem goes away when you disable the hardware-accelerated decoding option, which is enabled by default. Note that you need to restart After Effects after turning this option on or off, and you should purge the cache after the restart, otherwise previously cached frames from that footage will be used.

I've filed the bug and asked our developers to investigate. Apologies for the disruption.

 

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As most of you are aware by now, i am pretty much the king of stupid questions. I am sure that many on this forum will attest to the fact that the stupidity of my questions knows no bounds.

So I have to ask as to why you would be transcoding your h.264 files to ProRes in the first place. I am sure you probably have a good reason to do so. Just, it escapes me at this time.

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1 hour ago, Mark Romero 2 said:

As most of you are aware by now, i am pretty much the king of stupid questions. I am sure that many on this forum will attest to the fact that the stupidity of my questions knows no bounds.

So I have to ask as to why you would be transcoding your h.264 files to ProRes in the first place. I am sure you probably have a good reason to do so. Just, it escapes me at this time.

Hi Mark, no stupid questions... if they're actually genuine.
I'm in a huge fuckery where Premiere Pro CC 2019 keeps dropping linked media (mpeg2 and h.264) if/ when I reset preferences and/ or delete media cache. But this does not happen with the ProRes files also attached to the project. I've wasted the past 5 weeks full time on this! No more! I've converted 8k mpeg2 files in hundreds of folders and am now moving towards tens of thousands of h.264 files. Horrible process to so as to get back to the creative.

Alright so...
Turning off the hardware-accelerated decoding option in PPro gets around the problem. Unfortunately it does not help for AME.
Does anyone have a working around to somehow export thousands of file using PPro in the same way as AME?
Or do I just move toward Apple Compressor?

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There is a noticeable color shift in the transcoded file when using Compressor. Any way around this? Doesn't any of this shit work properly anymore?

Also, why is there no way to export file without the "Apple ProRes 422" file name? Just perfect for those who want more headaches when relinking media. I mean really, what asshole beancounters are breaking perfectly good shit that used to work properly?

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So the current situation is that:

1. You have H.264 footage, but it is not linking properly in Premiere

2. You can convert H.264 to ProRes with Adobe Media Encoder, but it bakes a black bar at the bottom

3. You can convert H.264 to ProRes with Compressor, but there is a color shift

4. IF you could convert to a properly scaled ProRes file, you can get it to work properly in Premiere.

Are all of those correct and am I missing anything major? If not, one option is to use ffmpeg for conversion. It's is my go-to program for any encoding or muxing tasks, and I've never had any issues with it encoding poorly or shifting colors. Is this an option?

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KnightsFan to the rescue. Thanks amigo, and yes you have the correct overview on the situation.
Can I ask you why you use ffmpeg when there are other options? I haven't used it for years but will have a look for it now.

Thanks again!

Edit:
DaVinci Resolve must have a batch converter... anyone with any experience? Surely these guys will get things right.

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No converter ever seems to have the options I'm looking for. I first started using ffmpeg to create proxies. After shooting I run a little python script that scans input folders and creates tiny 500 kb/s H.264 proxies with metadata burn in. I tried other converters but I had so many issues with not being able to preserve folder structure, not being able to control framerate, not being able to burn in the metadata I want, etc. I've also had issues with reading metadata--sometimes VLC's media information seems off, but if I use ffprobe I can get a lot of details about a media file.

I also use ffmpeg now to create H.265 files since Resolve's encoders are not very good. I can get SIGNIFICANTLY fewer artifacts if I export to DNxHR, and then use ffmpeg to convert to H.265 than if I export from Resolve as H.265.

And recently I did a job that asked for a specific codec for video and audio, the combination of which wasn't available to export straight out. So I exported video once, then audio, then used fmpeg to losslessly mux the two streams. And another little project that required me to convert video to GIF. It's become a real swiss army knife for me.

26 minutes ago, User said:

Edit:

DaVinci Resolve must have a batch converter... anyone with any experience? Surely these guys will get things right. 

Yes, Resolve has a batch converter. Put all your files on a timeline, and then go to the deliver page. You'll want to select "Individual Clips" instead of "Single Clip." Then in the File tab you can choose to use the source filename.

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Hey thanks for this KnightsFan, I appreciate it. It certainly sounds like you've covered good ground in trying to sort through your a/v issues. I start to get a better sense of python and command line scripts in order to get things done when the big shots cast their wide nets and side-lining the niche heavies. I'm using MediaInfo to get file info when Apple's Get Info fails to show much of anything. Copy Fold Tree (uses Apple's Script Editor) is doing a great job at recreating Folder Trees that I'm transcoding into.

You mention that you are not so thrilled with Resolve's encoder but let me ask you, would you use Resolve to encode h.264 to ProRes 422 if you wanted comparable results to what Compressor and AME give?

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I haven't used Adobe since CC 2015 so I have no idea how Resolve's encoder stacks against theirs. I suspect that it's just that their H.264 encoder isn't great and that they don't really focus on that as it isn't a "pro" codec like ProRes or DNxHR. To be honest, I don't know much about ProRes in general, but my impression is that there are fewer options, whereas H.264 is a massive standard with many parts that may or may not be implemented fully.You'd have to do your own tests, but I would doubt that Resolve's ProRes encoder is as bad as their H.265 one. Actually, to be fair, their H.265 encoder isn't even their product, you have to use the native encoder in your GPU if you have one, and if you don't, you can't even export H.265 at all I think.

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Good stuff, thanks.
Keeping yourself away from Adobe is an exercise in sanity. I'm with you that ProRes is an industry standard and that Resolve must have this right as rain.
Yes I'm doing my own tests to see what's what... I'm just about to give iFFmpeg a go with one test file... fingers crossed and thanks again for the tip and extra insights along the way!

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3 hours ago, User said:

Hi Mark, no stupid questions... if they're actually genuine.

Thanks for the reply, and yes, a genuine question on my part. Didn't realize that PP was prone to this issue (but I don't use it so I am ignorant of a lot of things about PP).

 

1 hour ago, KnightsFan said:

I also use ffmpeg now to create H.265 files since Resolve's encoders are not very good. I can get SIGNIFICANTLY fewer artifacts if I export to DNxHR, and then use ffmpeg to convert to H.265 than if I export from Resolve as H.265. 

Thanks for sharing your workflow when delivering. I know quite a few people complain about the h.264 encoding in resolve. Didn't know that h.265 is chock full of artifacts, too.

Hmmm.... looks like I am going to install ffmpeg soon. Seems so strange that the best way is to send it to an intermediate codec and then a final, but I guess that is the way it has to be.

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