w64 or wav for B-R, 48kHz/96kHz & video render

Gabonviper wrote on 9/1/2012, 2:23 AM
Hi,

I am creating my first blu-ray music video (MainConcept MPEG-2, 1440x1080-60i, 25Mbps video stream) in Vegas Pro 11 (a multiaudio four-track mix from various audio sources) and was wondering if it makes any difference whether I use the Sony Wave64 template or the Wave (Microsoft) one for the audio. Both sound the same to me, but are there any compatibility issues?

Also, should I render it as 48kHz or 96kHz? 16, 24 or 32 bit?

I will finish it in DVDA 5.2 and with the audio file rendered as 48kHz the four-hour 15 minute project now fits on two 25GB discs, with about two hundred megs of free space on each after menus and all.

Another question: The multicam video mix is a compilation of altogether 20 video sources (varying quality and frame rates) and the default Pro 11 gives for render is HDV 720-30p as those were the settings I chose for the project in the properties (1280x720, 29,970 NTSC).

Of course this template is no good for blu-ray, so I have already rendered the whole project with the MainConcept MPEG-2, 1440x1080-60i, 25Mbps video stream template and it looks fine on the computer screen and projected with a Full-HD projector onto a large screen. I haven't tested it on regular TVs yet, so I don't know if it this would be the right setting for regular TV-viewing in Finland.

The only thing is the project is now so huge I won't be able to add animated buttons to the menus in DVDA, as both discs would then exceed the space by about 500 megs.
Then the question: If I lower the output width and height of the template from 1440x1080 (pixel aspect ratio 1,3333 to 1280x720 (pixel aspect ratio 1,000), would this

a) affect video quality (I made test comparisons and they both look the same on the computer screen qualitywise, though the 1440 one opens to full screen whereas the 1280 one doesn't.)

b) reduce the size of the rendered file? (the 15-second test files vary surprisingly: the 1440 is 43 megs and the 1280 is 45,6 megs, so maybe I shouldn't change it, but then, would changing the resolution

c) affect playability in various devices (I watch it on PS3)?

Lastly, should I choose 1440x1080 or 1280x720 in DVDA for resolution in properties?

Any help appreciated. Bear with me and be gentle, as I am a novice ;-)

Cheers,

Marko

Comments

PeterDuke wrote on 9/1/2012, 5:20 AM
The audio should be as permitted by the Blu-ray spec. See the Wikipedia page for instance. Unless you expect someone with exceptionally keen ears to be listening, with the highest quality equipment, then something similar to CD quality should be adequate, such as 48kHz 16bit linear PCM. However, Dolby Digital will save some bits at the same quality which you could put towards your menu.

I suspect Finland, as in much of Europe, uses the PAL system, but most PAL equipment these days will play NTSC, so you could be safe there. (The reverse is not the case with NTSC, however.)

If you lower the bitrate of your video you will lower the visual quality. It is up to you to judge whether the degradation is negligable or not. You say that the source has a variety of qualities, but don't say what the best one is. There is little point in setting the output quality to be better than your source.

It is best to set your project properties in Vegas to your output, since you have more than one source type. Then render the audio and video separately to a suitable Blu-ray template and DVDA should make your BD without re-coding anything.
Gabonviper wrote on 9/1/2012, 6:51 AM
Thanks very much for the reply. The best source of the 20 video sources is a Panasonic HD video cam (1920x1080, 16269bps, 25fps) followed by iPhone4 (1280x720, 10519bps, 28-31fps) and a Sony WX-1 (1280x720, 9040mbs, 29fps). These three account for 70% of the close to three hours of concert footage.

So I should
a) retain the original project properties setting of HDV 720-30p (1280x720). Full resolution rendering quality: best.

b render the video file as MainConcept MPEG-2 Blu-ray 1440x1080-60i, 25 Mbps video stream (video quality: high), and change the template's default output resolution 1440x1080 to the project's original 1280x720.

c) render the audio as either PCM (wav/w64) or Dolby digital ac-3 (pro), depending on whether the reduced size is enough for the use of animated menu buttons. Luckily, rendering the full concert audio file takes only 5 minutes, (as opposed to almost 24 hours for the whole footage...), so I can easily compare the benefits of either format in DVDA.

Does that sound round about right?
Chienworks wrote on 9/1/2012, 8:15 AM
W64 should be avoided at all costs as there's no guarantee that any other software or player will recognize it. You are correct in that the quality is identical to wav. They are exactly the same format, except that the Sony software engineers hacked the wave header format to allow a 64-bit length format for storing much larger/longer recordings than wav can handle.

Generally there's no reason to use a higher audio format than your source. If your source is 48KHz 16 bit then you gain nothing by using either 96Khz or 24 bit. You'll only be wasting space on the disk for no purpose.
Gabonviper wrote on 9/1/2012, 10:26 AM
Thanks for the reply.

The best audio source used there runs through the concert and is 48kHz, so no need for 96kHz then.

But, contrary to what was said about Dolby Digital and PCM being of equal quality, I ran comparative renders using both ac3 and wav and the latter to my mind sounded not only louder but had also more range to it. Might be the multimix here, go figure, but in any case I think I'll go for wav.

But one question remains about the video rendering:

I have already rendered the video for both discs using the 1440x1080 60i template (as the list of templates did not have the resolution option of my project setting 1280x720) and in DVDA I chose to use the original resolution 1280x720 when rendering the image file. The result to me looks fine.
Each video file (25GB) took about 11 hours to render in Pro 11, so I wouldn't really like to redo it if there is no obvious benefit.

So the question is: will I gain better video quality if I render the HDV 720-30p project using Main Concept MPEG-2 Blu-ray 1440x1080-60i, 25 Mbps video stream as such and then reduce the template's default resolution in DVDA to 1280x720 at the image rendering stage as opposed to changing the Main Concept MPEG-2 template's resolution to 1280x720 already when rendering the file in Pro 11?
In other words, does it do any harm if I let DVDA do the reduction of the resolution when rendering the image file instead of reducing it in Pro 11 at the video file stage?

(Sorry about the wording - I hope you catch my drift - I hope I caught it myself ;-))
john_dennis wrote on 9/1/2012, 10:37 AM
"The best source of the 20 video sources is a Panasonic HD video cam ("

Pixel dimensions do not affect file size, only bit rate affects file size.

From your description, the highest source bit rate is 16 mbps. I'm assuming you missed a k in 16269 You could use the Sony AVC/MVC Blu-ray 1920x1080 template at the normal setting of 16 mbps with little loss of quality. If you're uptight about it, you could raise the bit rate. Be prepared for a long render. With no 1440x1080 source, that would not be my first choice as an output pixel dimension. No knock on MPEG-2, but you can get equally good video at a lower bit rate with AVC.

john_dennis wrote on 9/1/2012, 10:41 AM
"In other words, does it do any harm if I let DVDA do the reduction of the resolution when rendering the image file instead of reducing it in Pro 11 at the video file stage?"

Very much so. Do all your rendering in Vegas Pro 11. DVD Architect should not render anything except menus. Rendering in both would lower the video quality.
john_dennis wrote on 9/1/2012, 10:51 AM
Read the DVD Architect 5.2 Manual starting on page 197 for a list of all acceptable render setting that will pass through DVD Architect without re-encoding.
Gabonviper wrote on 9/1/2012, 1:58 PM
Most of the video is from the iPhone at 1280x720 with only about 10% from the Panasonic, but what you're saying using the 1920x1080 template will also be fine for the iPhone source so that the larger pixel size won't distort the iPhone footage or pixelate it? (May be a dummy question ...). As it is, the iPhone files actually look the best as they were shot right in front of the band, whereas the theoretically superior Panasonic files leave a lot to be desired in sharpness etc. So if Ihave to sacrifice anything with regard to quality, the iPhone lower res files will be prioritized.
john_dennis wrote on 9/1/2012, 2:28 PM
If most of the video is 1280x720-30p, for Blu-ray, I would render 1280x720-59.94p. That pixel dimension and frame rate is legal for Blu-ray but you will have to customize the render template in Vegas Pro 11. Change the media properties on the Vegas timeline to "no resample" for the 30p source source material.

You can find the "how-to" for customizing the render template here.
Gabonviper wrote on 9/2/2012, 4:02 AM
I customized the Main Concept MPEG-2 1440 25 mbps template according to your instructions(1280x720, 59,940, disable resampling, left the bit rates as such 30mbps) and ran a test with various sources (all of which 30fps) in it. It seems to look fine, but I'll compare it to a similarly modified AVC template with 16 mbps, and see if they differ. By the way, I left enable resampling on some of the clips and there doesn't seem to be any difference in quality.

But just to check: as for quality, should I now choose high, and say 20mbps as the maximum in the variable bit rate box (the best source has 16mbps) (what about average and minimum?). What about field order: upper field or none (progressive scan)?

Sorry about asking the obvious perhaps, but in 1280x720-30p, does the 30p refer to frames per second, progressive scan? The iPhone4 files are 1280x720x24, but if I understand correctly, the x24 refers to bits per pixel, and is of no relevance here. Most of the material in this project is 29 fps, even 680x480 ones, so are they also 30p?
So how do I know it is 30p? If the media properties for a clip on the timeline have progressive scan ticked and 29 fps, or 31,579 for some iPhone4 clips (their frame rates can vary a lot depending on lighting conditions), then it's a 30p clip?


Bear with me, please. And thanks a ton for the replies already given. I have learned a lot.
Tim20 wrote on 9/2/2012, 4:50 AM
Try the render with smart resample on. Not sure why you would want it off with mixed frame rates and up-converting.
Gabonviper wrote on 9/2/2012, 5:03 AM
Yes, I edited the above with reference to the resampling: I saw no diffference whether on or off. As there are thousands of clips in this movie, some a second long, I'd be happy not to have to manually disable resampling in each.
Tim20 wrote on 9/2/2012, 5:18 AM
Ok. Is GPU accl on or off? If on try turning it off. Also what type of CPU are you using?
The reason I ask is I have seen clips render with flicker and stutter when the number of rendering threads are maxed out in the properties. I can only assume that what happens then is Vegas is try to hog the CPU while other background services need some CPU. The default is 16 threads and may need to be lowered.

Oh and I just had a "duh" moment. You are rendering the audio seperate from the video??
Gabonviper wrote on 9/2/2012, 6:09 AM
The flickering happens only occasionally when viewed in DVDA, and not in the same place all the time. So it has to be the CPU?
specs:
win 7
64-bit
intel core i5-2500k 3.30GHz
RAM 8 GB

and yes, rendering separate
Tim20 wrote on 9/2/2012, 6:28 AM
Ok that CPU doesn't have hyperthreading. Try turning rendering threads to 3 that should leave one core for other tasks. Not sure it will work but anything is worth a try :)
Chienworks wrote on 9/2/2012, 6:39 AM
"Try the render with smart resample on. Not sure why you would want it off with mixed frame rates ..."

I don't know why one would want it on. With mismatched frame rates resampling can produce ghosting and doubled images, which looks awful. With it off, the frame rates are close enough that the occasional dropped frame won't be noticed.

"... and up-converting."

Resampling has nothing to do with frame size and resizing. It only affects frame rate, nothing else.
Gabonviper wrote on 9/2/2012, 6:47 AM
Ok, only thing: how do you do that?

Btw, I tried changing the project properties of the already rendered files for the blu-ray in DVDA from 1280 59,940 to 1440 29,970 interlaced and there didn't seem to be any difference in quality. (the render template was Main Concept MPEG-2 1440x1080 60i). If l now leave it like that for the image file render (and not render the image file as 1280x720), will DVDA then have to do any recompressing?

But then again: I ran various modified template tests and at least on my computer, the best video quality in DVDA seems to come with the AVC Blu-ray 1280x720 59,940 20 Mbps video stream template (smart resample on). No flickering, at least not in this 2,5 minute sample. By far the sharpest, too. And the smallest size (337 megs compared to an equivalent Main Concept render (also 20mbps, 1280x720 59,940) 351 megs.
The difference in size may be enough to allow the animated buttons I was after. At least it's worth the shot.
Tim20 wrote on 9/2/2012, 7:03 AM
My bad on the up-convert but I am not sure I agree on the resample issue. Yes it can possibly cause some ghosting but I have only seen it once in the last month. For the last month I have been mixing frame rates plus i and p footage. I check renders across multiple frames one frame at a time and don't see issues.

The big issues I see in Vegas when rendering is trying to push it too hard. When the CPU gets really loaded up the renders start showing flickers that included massive color change. Finally just turned GPU accl off (crashes too much) and threads down to 7. Problem solved.






Tim20 wrote on 9/2/2012, 7:07 AM
Render out of Vegas to the settings you would use to create dvd in DVDA.

CPU threads can be changed in Options/Preferences/Video/ Max number of rendering threads.
Gabonviper wrote on 9/2/2012, 8:25 AM
Just to make doubly sure:

since the highest bitrate of the clips is 16 mbps, there is no point in raising the bitrate in the AVC template to 20 mbps, as DVDA will then have to compress it to match the original highest bitrate?
What if I change the DVDA project properties to match the Pro11 render (raise the bitrate there to 20mbps)? Then there won't be any recompression?
To my eyes, the 20mbps version looks better than the matching bitrate, so...
Chienworks wrote on 9/2/2012, 9:30 AM
"as DVDA will then have to compress it to match the original highest bitrate?"

Not sure where you got that from. DVDA will only recompress if what it's given won't fit on the disc. Not only does DVDA not care in the slightest what the original bitrate was, but it has no way of even knowing.

Source bitrate and output bitrate have pretty much no relationship to each other.

16Mbps source rendered at 25Mbps will look better than rendered at 16Mbps.
25Mbps source rendered at 25Mbps will look better than rendered at 16Mbps.
25Mbps source rendered at 7Mbps will look better than rendered at 5Mbps.
3Mbps source rendered at 25Mbps will look better than rendered at 3Mbps.

25Mbps source rendered at 3Mbps will probably look better than 3Mbps source rendered at 25Mbps.

3Mbps source will look awful no matter what output bitrate you use, but it will look less awful rendered at 25Mbps than at 3Mbps. The question is, will it look enough less awful to be worth using 8 times as much drive space?

Rendering to a higher bitrate will always look better than rendering to a lower bitrate, but no matter what bitrate you choose it's not going to look better than the source. A lossy recompression is always going to take a quality hit, and Vegas really just doesn't do non-recompress renderings of most long-GOP material.
Tim20 wrote on 9/2/2012, 10:14 AM
Chien your statement about transcoding/recompression is a little misleading. See note on page 25 of the DVDA Pro manual.

Now having said that try using the Sony AVC/Bluy ray 16Mbps codec. In customize template leave the bitrate alone and under the system tab/format select MPEG 2

I just did a short frame by frame comparison of it and the .avc and noticed some slight artifacts in the .avc.
Laurence wrote on 9/2/2012, 11:24 AM
I have an app on my iPad called "Dog Whistler" that will generate sine waves at various frequencies. My hearing is gone slightly before 12k and I find that that is better than most of my adult friends. My children can hear up to close to 16k. 96k is useful for things like recording sound effects that are going to be slowed down and for avoiding aliasing on on things with lots of high frequency content, but for the most part, is overkill for a human audience.
john_dennis wrote on 9/2/2012, 3:22 PM
"To my eyes, the 20mbps version looks better than the matching bitrate, so...

"When the deal is on the table, stop talking."

This is an old marketing adage that fits well here. You've picked the video that you think looks the best. 20mbps is lower than your original target bit rate of 25mbps and should give you the space you need for animated menus. Start renderning, it's going to take a while.

Homework Assignment:

Read all you can until you understand PAR, frame rate, sample rate, bit depth, square pixels, progressive, interlaced, etc.

Memorize Appendix B of the DVD Architect Manual so you know the limitations imposed on you by the Blu-ray and DVD specifications.

Download Mediainfo so you can look at your files to see what the internal characteristics actually are.