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judas beast
compressor vs quicktime conversion
on Jul 12, 2007 at 2:08:08 pm

I'll run past my experience so far step by step, it may shed some light on what i need to work on - but I'm having a really hard time getting crisp movs using compressor.

1 - I'm working with PAL compositions created in After effects (720x576)- rendered out as lossless uncompressed animation quicktimes... look great in quicktime player although typically squashed due to pixel ratio

2 - I import the lossless animation into FCP, it looks fine and sharp on the timeline, making sure sequence settings use animation codec (forgot to change this from DV before and animation looked rough in the viewer)

3 - from FCP file menu: export using "quicktime conversion", I then choose the pre-set: "broadband high", click the options and the default compressor quality is "high" and set to "H264". Data rate I set limited to around "150 kbits/sec" (i used to leave it set to "672 kbits/sec" as default but found by lowering this value i got much smaller file sizes without much loss of quality) - frame size is set by default to: 480x360, I leave this alone.

5 - now trying to use compressor - mimicking the pre-sets that previously worked well with quicktime conversion. I click on source setting and select pre-set: "web download, quicktime 7 compatible 800kbps" I have experimented with limiting data rate from 672 to 150 kbit/secs, also i check frame size - set by default to 480x360, i leave this

The trouble is results in compressor are just plain worse than before using FCP's QT conversion - I have no idea if there is some sort of small box I need to tick or un-tick, the original uncompressed file looks crystal clear... I'm slowly going mad here - cant see why it would look so much worst in compressor apparently using the same settings?


um, yeah!


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Craig Seeman
Re: compressor vs quicktime conversion
on Jul 12, 2007 at 4:52:48 pm

Compressor and Quicktime Conversion should look exactly the same since it's the same "engine."

I really think you're having an issue understanding the settings.

You need to be able to identify your target and then use the appropriate preset or customize the settings (much better).

What is the typical speed of the internet connection of your target?
Will the viewer likely have QT 7?
How powerful at decoding is the viewer's computer likely to be?

Once you know (or guess) that, you need to consider exactly what the content is of your source file and then modify the settings to compromise your quality the least.


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judas beast
Re: compressor vs quicktime conversion
on Jul 12, 2007 at 7:12:30 pm

"Compressor and Quicktime Conversion should look exactly the same since it's the same "engine."

I'm aiming to create a mov good for fast broadband, powerful computer.
The weirdest thing for me is that H264 does look good but only when i use export from FCP: "using quicktime conversion" - looks good even when i when i lower the bit rate to 150 kbits/sec...

...BUT: when I use use the same settings to export: "using compressor" it looks rubbish.

very odd!

cheers for your help


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Craig Seeman
Re: compressor vs quicktime conversion
on Jul 13, 2007 at 2:39:10 am

[judas beast] "Data rate I set limited to around "150 kbits/sec" (i used to leave it set to "672 kbits/sec" as default but found by lowering this value i got much smaller file sizes without much loss of quality) - frame size is set by default to: 480x360, I leave this alone."

Generally a data rate of 150kbps is going to be WAY too low for a 480x360 frame size but it really depends on what's happening in the content.

Data rate combines audio and video. The H.264 High Broadband preset is 800kbps combined in both Quicktime and Compressor.

I used my own test file (DV, self contained export from FCP to my desktop) and used the Quicktime Broadband High setting in QT and in Compressor and the both look EXACTLY the same, have the same file size/data rate.

Sorry, but I can't help but think you're doing something other than using the same setting in Quicktime Conversion vs export to Compressor.

If you send me your source I can do a test and send you back the encodes if you'd like.


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