Broken Sword MPEG performance

Subforum for discussion and help with ScummVM's PocketPC/HandheldPC port

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jvprat
ScummVM Developer
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Post by jvprat »

From what I've read, the DXA codec is lossless. I think you should be careful with the scaling of the pngs, so it doesn't add new colors from the interpolation and the output image is written in 256 colors (better if they're the same colors of the original image).
clem
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Post by clem »

jvprat wrote:From what I've read, the DXA codec is lossless. I think you should be careful with the scaling of the pngs, so it doesn't add new colors from the interpolation and the output image is written in 256 colors (better if they're the same colors of the original image).
just wondering, is that one 256 color palette throughout the whole animation, or can the palette change if for example a scene changes?

clem
fingolfin
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Post by fingolfin »

The palette can and does change.
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robinwatts
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Post by robinwatts »

The DXA codec is lossless, yes. I did the scaling of the PNGs using the RAD game tools as it decoded the images, so my belief is that it doesn't bloat the palette, and minimises the changes. (I've just checked, and the files only contain one palette change, at the start).

On the other hand, if it *did* increase the palette due to interpolation, then at least the quality would be better.

I wonder, is it possible that the DXA files online were generated from the 'SMACKERLO' source rather than the 'SMACKERHI' source?

Robin
Kirben
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Post by Kirben »

Make sure you are using DXA encoder from tools section of SVN, as there were compression improvements since last tools release.

The DXA encoder reads the width, height and flags (for scaling) directly from the header of the Smacker file. So make sure you are adjusting those settings in source code, since you are using a specific resolution, with added scaling too.
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robinwatts
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Post by robinwatts »

Using the latest version of the encoder has indeed helped - thanks!

Down to 47 Meg now. For anyone interested the files can be found at <http://www.wss.co.uk/scummvm>.

I'll try and do the BS2 files too over the weekend, and tidy up and submit the patch that makes these run full screen.

Robin
clem
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Post by clem »

robinwatts wrote:I wonder, is it possible that the DXA files online were generated from the 'SMACKERLO' source rather than the 'SMACKERHI' source?
unlikely, as the low quality smacker files are partly of lower resolution (e.g. intro.SMK 480x300 instead of 640x400)

err, I can only speak for the mpeg files here - sorry

clem
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