How to render for web?

L

Lor

Well-known member
Okay, I've finished editing a 4 minute long footage. How do I render so that I can put it on the web for streaming? For whatever codec or settings I've used (for web), the rendered file looks too dark and crappy. It does not look anything close to the version I've edited.

Help is appreciated.
 
Actually I use Avid but I exported as QTF then I use ProCoder to render the file to Web. This is where it does not matter what settings I choose, it always turned out bad. The aspect ratio is wrong and coloring is wrong. I use PC and I did try Quicktime, Windows Media but still all look bad.
 
Try dropping the contents of the attached ZIP file into your C:\Documents and Settings\All Users\Application Data\Grass Valley\ProCoder 3\User Presets folder, then select the H264 960x540 2.5Mbps preset from the User category. You'll also want to adjust the output location to something that is valid on your system, and if the material you are encoding is complex, you may want to bump the bitrate up or lower the output resolution.
 

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Just FYI, that preset requires QuickTime 7 Pro to be installed, without it you can't encode H.264. If you haven't kept your QuickTime up-to-date, I would install the latest version from Apple's website before you try that preset.

The preset uses multi-pass encoding, and Procoder has no idea how many passes QuickTime will eventually make. Unfortunately Procoder's time estimates are based on a very pessimistic assumption of 100 passes, so don't freak out when you see the time remaining. In my experience, QuickTime will typically make six to seven passes, the last of which completes quite a bit faster than the previous ones.

If you find that 960x540 is just too large for the web or you use 720P source, try setting the dimensions to 640x360. The smaller resolution usually holds up quite well even at 1Mbps, which virtually all broadband connections can stream.

I also have WMV presets that I can share if you want them.
 
Okay, I got this error after an hour and 55 minutes 58 seconds.

QT Export: Invalid duratin.

I got it twice trying.
 
I've not experienced that myself -- try modifying the preset and turning off the "Pass source duration to QuickTime exporter" checkbox.
 
I got the same error. After 1:56:48 the QT Export: Invalid duration error popup again.

Will you give me the Windows Media preset? Perhaps I can try that.
 
I've used the QT preset many times and never had that error -- try it with another source file, or a shorter one. You can also use the Advanced button on the source and set in and out points to select a section of the source file.

Anyway, the WMV version is attached.
 

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Okay, the WMV version works fine although the color seems a bit dark. Any idea why the rendered verison here looks darker and more saturated than when playing in the NLE software?

By the way, thanks so much for the help.
 
I used Edius to output SMPTE color bars as a 1080p DVCProHD AVI file, and then encoded that using the WMV preset.

I then pulled the AVI and WMV files back into Edius and compared the IRE levels of the generated color bars, the AVI file, and the WMV file using the Edius vector scope -- the levels are identical. I also compared the YUV values, and those too were identical for every one of the bars.

You may want to conduct a similar experiment using whatever NLE you use, but the Windows Media Encoder shouldn't be altering the colors or brightness levels. I would in particular check the file that you are feeding into Procoder to make sure that it is identical to the material from your camera.

If the IRE and color values are identical, then you're looking at a display problem. The Hardware Video Overlay of most video cards can be adjusted independently of the normal desktop colors, and NVIDIA for example boosts the gamma by default when you install their drivers. Anytime a video player is configured to accelerate video playback using the HVO, the colors will be skewed, and more so if the driver applies psychovisual enhancements.
 
Again, thanks so much. I'll check those settings and perhaps experiement a bit as you suggested.
 
Okay, I think the problem may have to be in ProCoder. I tried rendering in MPEG2 - DVD - NTSC (mastering quality) settings and the color still looks too dark as showing below.

Procoder_rendered_test_color.jpg


And I then I try open the QTF .AVI file and the picture looks right like the one below.

HD_Test_color_quicktime.jpg


The only difference is that the QTF Still Grab is HD quality and the rendered version from ProCoder is standard quality and aspect ratio is display incorrectly in here. However, I don't think that should change the color brightness of the picture. The settings that you gave me produce the same color darkness as showing in here. The picture should like the second image I post here.

I like to add that even when during the conversion process in ProCoder, the picture even looks darker, more like the rendered version.
 
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QuickTime has had inconsistent gamma handling for as long as anyone can remember. I'm certain that your problem is QuickTime's fault, and not Procoder's -- my tests prove that neither Procoder nor Windows Media Encoder changed the gamma, or the luma values would have been different. Also take a look at the gamma section of this article.
 
Okay, so I assumed the gamma settings that article talkes about is during the process of exporting from FCP, correct? What is the difference between Quick Time Reference and Quicktime Movie? I'm using Quicktime Time Reference.
 
A quicktime reference only references to your raw material much like your timeline in your NLE. This means you must keep your raw material in order for it to work. So it's not a digital master you can keep for backup.

And for your encoding: is it set to RGB?
 
Thanks, balster. That's what I thought...but I'm not exactly sure.

Anyway, where to do I set the RGB? When I export out of Avid as QTF, I believed the setting was 601. I did try with RGB export in Avid but when comparing the QTF of 601 and RGB the RGB looks a bit darker then the 601 so I'm not exactly sure which one I should use. I have not tried rendering the RGB QTF in ProCoder yet though.
 
601 is a SD colorspace, whereas HD uses 709. That may explain your problem right there. Procoder does have filters to handle colorspace expansion and compression that you can access using the Advanced button and then going to the Video Filters tab.
 
Okay, so where do I set this 709? Is this in Avid when exporting or in Procoder when rendering?
 
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