My XH-A1 - Artifacts - Still Mediocre Quality

M

MelonDome

My XH-A1 - Artifacts - Still Mediocre Quality - Maybe cuz of OLD laptop?

My problem:

- I never get crisp clear quality.

- My pictures have some artifacts in them.

- This goes for SD and HDV

- The captured HDV footage is fine when I look at it. After the rendering is whe the SD and HDV are wierd.


What is my Setup:

- I shoot in HDV 24F 2:3 Pulldown.

- My laptop is OLD. Toshiba, 1.6 GHZ, 512MB, 80GB. Could this be the problem idk?


What is my procedures?

- I make sure my XH-A1 is shooting in HD, 24F.

- After I finish recording I connect it to my laptop.

- I use HDVSplit to capture my footage.

- I use pulldown.exe succesfully

- I open Sony Vegas, and import my footage.

- I render mpeg 2, NTSC HDV 24p.

- I also downgrade it to SD to see how it performs. DVD Architech 24p NTSC Widescreen Video Stream

- I have used AVI for windows before, but it is even more terrible quality.


My Video Samples:

XH-A1 SD 24f, downgraded from HDV.
http://www.megaupload.com/?d=A25WPJRI

XH-A1 HDV 24f
http://rapidshare.com/files/134208240/Test_HDV.mpg.html



In Conclusion:

You see these films at film festivals, online, on DVDs; they all have good quality footage. No distracting pulsing pixels/artifacts ect. I know it isn't my XH-A1, and we had a discussion like this quite a while ago. Maybe this time if I can provide you guys with more extensive information (sample clips/procedures) you might be able to help me better.


btw.. I know.. I have had alot of problems recently. Murphy's Law hit me pretty hard. I can't help it. :(
Just remember, at some point in the past, you guys were all in my noob shoes ;).
 
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If you're talking about the shimmering pixels around objects, those are very common MPEG compression artifacts. When transcoding, what is your bitrate and how many passes are you using? The good news is that what you are seeing is not a result of your laptop hardware; it's the compression algorithm.
 
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Forgive me for being such a noob. You say transcoding, bitrate, and passes, where does one find all of this? thank you

edit: I installed this thing called lagarithloss codec, and used that during my compression on pulldown.exe. I dont know how to check my bitrate or passes though?
 
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No worries.

Bitrate is the amount of digital information moved every second (in Mega, aka "millions" of bits, or binary digits, either a zero or a one). The higher your bitrate, the more information you can have in your image and/or audio. The more information available, the better the quality.

G = Giga or billion
M = Mega or million
b = bits
B = bytes (8 bits)
s = seconds

Thus, 10Mb/s = Ten Million bits per second.

Then you have CBR or Constant Bitrate and VBR or variable bitrate. Variable changes the rate depending on scene complexity and takes less storage space for a comparable video image. I believe most standard DVDs are around 4Mb VBR and the "Superbit" Discs are around 7Mb if I recall correctly. In contrast, Blu-ray can handle up to 40Mb/s for video alone. Variable can have more than one pass in the encoding process, so this is why I asked about the number of passes.

MPEG is a lossy algorithm, so you are going to lose some information when you convert your video no matter what. It's like when you take a Camera Raw image from your digital still camera and turn it into a JPEG. Depending on the quality of the compression and the size of the resulting compressed image, you can get a similar effect in your photos. So, the less the compression, the better the image quality, but the higher the storage requirements and bitrate. In the still image example, Photoshop does a heck of a lot better at maintaining image quality when compressing to JPEG than Microsoft Paint, which will create a similar artifacting to what you see in your video. The sophistication of the compression algorithm is directly dependent on the resulting image quality.

Transcode is literally "translating code" from one format to another, where it first decodes the stream and then re-encodes it into a different language.

The settings you need to look at in Vegas (which, unfortunately, I am not familiar with) are the export settings for "mpeg 2, NTSC HDV 24p". You should ideally have a selection somewhere for quality that will allow you to adjust the bitrate.

Someone familiar with Vegas will need to assist further. I can tell you where to go in Premiere Pro 2.0, but not Vegas. Sorry.

EDIT: If it's any consolation, you can see these same types of compression artifacts if you zoom in on many DVD movies.
 
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I haven't got time to look at the images, too busy at the moment... but chances are that you're causing the artifacts in post production and exporting

In post production SD degrades in quality the more times it's rendered... because each time you render it compresses the material into the default codec. The filters that seem to do the most damage are any which involve image manipulation (basically any of the effects you'd normally do as part of the online edit in a traditional workflow).

The other place that you can mess up your material is at export... if you're exporting for the web you're getting into codecs than can range in quality between superb and dreadful merely because of the way set them up...

In my opinion exporting video for the web is a black-art where there is always more to learn.

If you want to start to get a clear idea of how to improve your workflow it would be worth reading "Rebel Guide to Film making"

Now, Stu who wrote the book is a real advocate of colour correcting and compositing in AE... but there are other options... what it will do is start to give you an idea of the fragility of DV footage and how to protect it in post production.
 
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Although, clive, the degradation in rendering is usually caused by compression from "lossy" codecs, such as mpeg 1,2,3,4 codecs. Thats why it is crucial, at the earliest point in the post process, to get to at least a lossless or visually lossless codec like Lagarith, HuffyUV, Cineform, or some other. Ideally, we would all use uncompressed codecs, but the amount of data is far too much to work with and store. An additional advantage to immediately transcoding to lossless and continuing to render lossless the whole way through is: generally much better color space accuracy, more preserved detail, and more accurate and, frankly, better looking effects, grading and transitions. The downside is lossless is still a lot of data to store.
 
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I would be curious to know what your guys' rendering settings are?

All im trying to do is make my SD DVDs have the same quality just as I shot the footage. No artifacts, or pixilation.. I want it to be just as if I rented a DVD.

I dont understand what im doing wrong and its so frustrating. There are all these indy films on DVDs and they did it perfectly. Its sad, cause Ive seen porn films that have better quality than my rendered footage.

Everytime I render my video is really small, it doesnt even fit the screen, when I put it to full screen you can see all the pixelation and artifacts.
 
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MelonDome said:
I would be curious to know what your guys' rendering settings are?

All im trying to do is make my SD DVDs have the same quality just as I shot the footage. No artifacts, or pixilation.. I want it to be just as if I rented a DVD.

I dont understand what im doing wrong and its so frustrating. There are all these indy films on DVDs and they did it perfectly. Its sad, cause Ive seen porn films that have better quality than my rendered footage.

Everytime I render my video is really small, it doesnt even fit the screen, when I put it to full screen you can see all the pixelation and artifacts.
Click to expand...

And you will see the same thing if you upscale a DVD without a smoothing filter. What you are seeing is normal. Render to a DVD disc and play it on your TV screen and you won't see them as much. Like I said previously, if you zoom in 200-400% on a JPEG image, you will see the same thing.

I use 7Mb CBR and 4Mb VBR 2-pass depending on the project.

Go rip a commercial DVD segment to an AVI file and then zoom in on it the same way you're doing with your video.
 
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Knightly I tried the "Print Screen" on windows a dozen times, it wont save a screenshot of video, even if its paused or stopped.

Heres a picture from another forum showing artifacts... this is also in my footage.

Screenshot of Artifacts - http://www.pichotel.com/pic/2999dHTAP/140077.jpg



This 5 second video shows how it has pixelation, and not clear, refer to the above image for what my artifacts are like.

Its a 4.23mb file. It should take a second to download.

Video of Pixelation - http://www.megaupload.com/?d=XTI7XVAY




@VPTurner: I understand the concept that you are talking about. The more you zoom in, the worse quality something gets. However, the question is, how does one render footage so this does not happen? How do those people who submit their films to festivals, DVDs, how do they make it so their films are perfect at full screen? Check out my 5 second clip if you can! thank you
 
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Got the whole file, can't view it :(

The image though just looks like stair stepping along the edges. This would be due to the fact that SD is a very low resolution format, if that's in fact the problem portion... assuming your output looks that way, not just the footage within the editor. (left side of image)

The right side looks like compression noise. You should be able to export a single frame form your editor though so we can see the actual issue you're having. If it's just occurring in the editor, it could just be not showing you full res footage to make the editor run faster so you get more of a real time experience.

Unsure about the PC solutions and their particulars.
 
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MelonDome said:
@VPTurner: I understand the concept that you are talking about. The more you zoom in, the worse quality something gets. However, the question is, how does one render footage so this does not happen? How do those people who submit their films to festivals, DVDs, how do they make it so their films are perfect at full screen? Check out my 5 second clip if you can! thank you
Click to expand...

I did watch your pixelation footage. I told you this is common with MPEG. Have you created a DVD and watched it on your TV yet? Take that same disc and drop it into a PS3 where it will upconvert with a smoothing filter, and you won't see as much of that pixelation. Or drop your desktop resolution to 800x600 so it's not scaling it as much. Or keep it as high definition footage and get a Blu-ray burner.

The stair step pattern is a different story. And you can see examples of that in commercial DVD movies, too. Anytime you scale something to a lower resolution (and compress it), you risk the chance of this happening. Welcome to the world of digital. Now you know why some of the professional equipment costs tens of thousands of dollars.
 
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Very interesting. I will never get perfect quality then unless im shooting HD and putting on on a Blu Ray.. It makes me wonder how people shoot with DVX100s in 24p and send there films to film festivals with such outstanding quality...

Im assuming im going to have to shoot at 60i HD and downconvert to 30p SD if I want the quality im looking for.

Thank you all of you.

edit: I put it on a DVD, and played it on my TV, and the quality was good. Just like a SD DVD. A tiny bit of artifacts/ "stepping" on some lines but it was fine. I guess computers/laptops dont do footage justice. Thank you
 
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MelonDome said:
Very interesting. I will never get perfect quality then unless im shooting HD and putting on on a Blu Ray.. It makes me wonder how people shoot with DVX100s in 24p and send there films to film festivals with such outstanding quality...

Im assuming im going to have to shoot at 60i HD and downconvert to 30p SD if I want the quality im looking for.

Thank you all of you.

edit: I put it on a DVD, and played it on my TV, and the quality was good. Just like a SD DVD. A tiny bit of artifacts/ "stepping" on some lines but it was fine. I guess computers/laptops dont do footage justice. Thank you
Click to expand...

When it's in that little window, it looks pretty good. But then you blow it up to full screen and you can see all of the compression artifacts.

Playback on a computer is very much dependent on the graphics card's capabilities. All of the newer ATI cards do a pretty good job. If you pick up a copy of the HQV benchmark (http://www.hqv.com/benchmark.cfm), I'll bet your laptop gets a low score.

On a side note, the format you submit to a festival doesn't always have to be DVD, does it? If you take your raw, uncompressed footage and transfer it to film or Beta, I'd think it would look pretty darn good compared to MPEG2.
 
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