Low Quality on Dissolve Transition with Photos

[mattgx]

I'm using adobe premiere cs 4. I have a thread here: http://forums.adobe.com/message/2067753

I'm currently trying to export as an uncompressed AVI with YMMV (or something like that) video codec to see how the quality is there.

If anyone has any tips, greatly appreciated. I'm about to throw in the white flag and accept that DVD quality and high quality photos don't play nice.

Thanks

[mattgx]

Yeah, uncompressed AVI still doesn't look the greatest. Ok, I'm officially about to throw in the white flag. I'd like one more person to confirm that the state of DVDs and high quality photos with transitions/movement don't play nice and aren't as sharp... if possible (so I know that this is an actual issue and not just my lack of ability).

Thanks

[poisondeathray]

DVD spec is the limitation, if you mean DVD-Video. 720x480 is low resolution, nothing you can do about that. Your high def, high quality photos get resized and lose a lot when reduced to 720x480

One option is to make a higher def version 1920x1080 on blu-ray or DVD5/9 media playbable on a blu-ray player. Looks much nicer

[mattgx]

Ah, yes, I mean the DVD spec. Thanks poisondeathray. Yeah, I thought about blu-ray but I am sending this to some family and friends and regular DVD is probably what my audience has at this point. In that case, I think I'll just accept the low quality and go with that.

[filmboss80]

There is no useful information provided here. Certainly, if the photo is captured at acceptable resolution, there is no reason it cannot look equally as sharp as video footage. But, of course, as poisondeathray said, you are dealing with 720x480 resolution; so while the photo should look as good as motion footage within a DVD, it won't be as sharp as a high-resolution image on your computer display.

I would be interested in knowing your specific Premiere video presets, as well as your still image settings in the timeline. Are you applying motion to the stills? Is Premiere trying to squeeze the stills to a specific aspect ratio? Are there interlacing issues? What are the dimensions and dpi of a typical still you are using? It is hard to dispense advice without knowing your sources and methods.

[mattgx]

Thanks filmboss80. I'm going to respond one-by-one...

"I would be interested in knowing your specific Premiere video presets, as well as your still image settings in the timeline."

My sequence is standard 48Hz DVD, 29.97 fps, progressive. Still images were 2000px on the longest side and resized. The video I'm encoding is mpeg2, quality 5, bitrate 8 CBR... I've also tried VBR min/avg/max at 8Mbps for kicks, same thing.

Are you applying motion to the stills?

Yes, some photos have motion, some don't. The video is 23 minutes. 200+ photos. So, some have motion, lot of dissolve transition.

"Is Premiere trying to squeeze the stills to a specific aspect ratio?"

Not to my knowledge. I don't see distortion, just fuzzy.

"Are there interlacing issues?"

No, I am doing everything (sequence and encoding) progressive/noninterlaced.

"What are the dimensions and dpi of a typical still you are using?"

2000px on the longest side. Not sure on DPI, they're from a 10MP camera... higher than 720x480 for sure.

"It is hard to dispense advice without knowing your sources and methods. "

Understood. Help me by asking specifics like you did. Hopefully my responses provide some insight.

Note that overall I only see the fuzzy during the dissolve transition. I don't see any flickering (progressive fixed that). I do see some fuzzy in a little bit of the photos while they're moving.

I'll refrain from burning 30 DVDs until I can confirm from a few more people that either A) I'm doing this wrong, or B) I'll need to tolerate it because of the DVD spec.

[filmboss80]

When opening Premiere, try a DV preset for the project. You can always export the timeline to DVD later when you are finished editing. In your Project>Video settings, don't apply any recompression. Are you using the standard Premiere cross dissolve effect for the transition, or another type of dissolve? It is difficult for me to get more specific, because most Premiere users (myself included) manipulate stills with AfterEffects or a plugin like StageTools Moving Pictures. I can only tell you that I don't have the problems you do. Your version of Premiere is top-of-the-line professional software. (Oh, please don't tell me you are using a demo version.) It does not make crappy images unless there is an improper setting or application somewhere.

[mattgx]

You mean a DV preset for my sequence? I use DV-NTSC, Standard 48Hz, and I change it to progressive.

Yes, standard Premiere cross dissolve effect for transition.

Hm, I'm not familiar with manipulating stills with AfterEffects or a plugin like StageTools, heh, I'll have to look into that.

Well, that's good to know that you don't have these problems. That means I won't end my quest for figuring this out.

Heh, I do have the 30 day trial... I am coming from Premiere Pro 2 (took about a year+ off editing) and I wanted to give CS4 a whirl on the trial before I buy. Will buying it make a difference? I can do that if need be... but I thought it was fully functional for 30 days.

Any other tips? Should I link you to a (small) MPEG2 with a few transitions/images so you can see what I'm talking about?

Thanks -

[mattgx]

I did make a little snippet in an MPG file suitable for DVD, quality 5, CBR 8. If anyone here would like me to PM them a URL, please let me know. I'm not sure if it's just me or if the quality issues are obvious... either way, the help is appreciated.

Thanks

[jagabo]

If only the transitions are are a problem you have too low a bitrate.

[mattgx]

Thanks jagabo. I tried CBR 8Mbps and VBR 8Mbps min/avg/max.. and also VBR min/avg/max 3/5/7 and it still looks the same.

I just PM'd you a URL with a little example of what I'm talking about. I like it when someone looks over my shoulder and either says, "I see it..." or ... "I don't know what you're talking about, it looks fine."



Thanks

[filmboss80]

Are you doing long dissolves between stills? With long GOPs and lots of B-frames, MPEG2 encoding gets tricky on dissolves. (Best to keep dissolves short. ) For a 23 minute video, CBR at a bitrate between 8 and 9 Mbps would be helpful, and your GOP structure should be I and P frames only.

Gotta go for the weekend. Don't have time to look at a clip.

[mattgx]

Dissolves are on average 1 second. Most go from black to a photo.

How do I set the GOP structure? I have this for GOP settings:

M frames: 3
N frames: 15

That's all I see... I did try googling GOP to learn more about it. I'll do some more research on that. If anyone else has any other tips, it is appreciated. In the meantime, I'll look into GOP.

Thanks

[jagabo]

Those settings should be OK. Note that a large part of MPEG compression is not encoding parts of the image that don't change from frame to frame. Transitions like cross fades are especially tough because every pixel is changing in every frame.

I'm downloading your sample now...

[mattgx]

Thanks jagabo. I was trying that same snippet with different GOP settings just for kicks (8 M frames N frames: 15). I've played around with every other setting except this.

[poisondeathray]

Is it the same result with the uncompressed or losslessly compressed output that you mentioned in the 1st post? If it is, then it's not the fault of MPEG2 or MPEG2 settings. If there is an improvement, then it's possible you can tweak the encoding settings

[jagabo]

Your problems aren't from the MPEG encoding but the resizing algorithms used to zoom in/out and pan. If there are different resizing filter options try a precise bilinear (a little fuzzy), precise bicubic (a little sharper), Lanczos3 (even sharper). How big are your source images? I suspect some of them are rather small. Ie, not 3000x2000 pixels (which can be panned smoothly and downscaled) but maybe 640x480 or less. Images that small with a sharp resizing or panning filter will flicker a lot.

[mattgx]

@poisondeathray, what's an uncompressed/losslessly format with video? Uncompressed AVI?

@jagabo, I didn't see any options on the transitions... it was just a basic dissolve. Maybe I could try another type of dissolve and see if I have those options, I can play with that. Source images are large. They are 2000 pixels on the longest side exported from Adobe Lightroom (they were resized to fit in the frame). If it was 640x480, I could understand the quality issues. So you do see what I'm talking about I imagine?

Thanks a ton!

[jagabo]

The bitrate is a constant 8000 kbps. There is a little macroblocking in the fade-to-blacks. But that's to be expected. Look at similar shots on any commercial DVD, you'll see the same thing.

I think the video is over sharp for what you are doing. I don't use PP so I don't know if that's the best it can do. Try blurring the images before importing and/or use an anti flicker filter.

Exactly what do you mean by "low quality"? Are you referring to the macroblocks? The flickering in the zooms and pans?

Since you don't have any fast action you should try encoding at 23.976 fps with 3:2 pulldown flags. That will stretch your bitrate further (fewer frames per second) and reduce the macroblocks a bit. It won't help with the flicker though.

[poisondeathray]

mattgx - the uncompressed AVI that you mentioned in the first post (assuming you did it correctly) would be "uncompressed", so doing this test would help rule out MPEG2 artifacts or low bitrate, or encoding settings. It would then leave either your workflow, resizing algorithm, or limitation of DVD-Video resolution as the culprit

In your workflow how did you do the scaling? (i.e. did you use automatic scaling or pre scale beforehand?). AFAIK , Premiere has limited choice in scaling algorithms

For the flickering you can try playing with the anti-flicker settings in the motion effects panel, or prescale with a softer algorithm as jagabo suggested

[mattgx]

@jagabo, ah, I have not heard of macroblocking. If I understand correctly, maybe VBR would be better with min at 3, avg at 6, and max at 8. Macroblocking is occurring because their isn't enough bandwidth, if I get all of this. I should try that.

I've tried anti-flicker to blur the images but it blurs it and I've been trying to avoid that.

I'm probably referring to the macroblocks. eg. the blocks that show during the transitions make the transition look fuzzy and not clean. There is also a little bit of macroblocks on the moving images (such as the moving tree).

I'll try 23.976. I don't see too much flicker, just the fuzzyness.

@poisondeathray, gotcha, that is a good idea. I did scaling via photoshop "scale frame to size" and I scaled some images more than that by adjusting the size in motion effects panel. I don't see too much flicker.

Hmm, thanks for looking guys... this is really helping me learn and resolve this issue.

[jagabo]

@jagabo, ah, I have not heard of macroblocking. If I understand correctly, maybe VBR would be better with min at 3, avg at 6, and max at 8. Macroblocking is occurring because their isn't enough bandwidth, if I get all of this. I should try that.

VBR won't help unless you allow peaks over 8000 kbps. The idea is that parts of the video that need more bitrate will get more, parts that need less will get less, but the average will come out the the value specified. If you don't allow peaks over 8000 kbps then no frame will get any more bitrate than your 8000 kbps CBR encode. Ie, your 8000 kbps CBR encode is all 8000 kbps peaks.

I'm probably referring to the macroblocks. eg. the blocks that show during the transitions make the transition look fuzzy and not clean. There is also a little bit of macroblocks on the moving images (such as the moving tree).

Macroblocks are 8x8 pixel blocky artifacts. Here's an 8x nearest neighbor (aka "point") enlargement to highlight the blocks (one block marked):



I found the flickering far more objectionable than the minor macroblocking.

[mattgx]

Ok, uncompressed AVI shows the same thing that I see in mpeg2. Alright, I think this means that I'm going to accept this and go ahead and burn 30 copies and start distributing them. If you have any other tips, let me know. I think I may start burning tomorrow.

If this thread lives on and someone else has any light to shed, I'd love to learn for any future projects.

In the meantime, thank you everyone. Boy have I learned a ton.