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CodecCompTesting: Difference between revisions
→Planned Work (specific)
(Created page with "= Code Compression Testing = == High Level Goal == The goal is to create a framework for testing image compression. We should be able to create data sets for any given codec...") |
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* Switch data output to RD curve data | * Switch data output to RD curve data | ||
* Add graphing capabilities | * Add graphing capabilities | ||
* Port some existing quality metric options to C programs. We don't want any more MATLAB programs, they're slow and introduce frustrating dependencies. | |||
* Add to collection of images we run tests on. | * Add to collection of images we run tests on. | ||
== Planned Work (specific) == | == Planned Work (specific) == | ||
* | Methodology | ||
* [Fixed by moving to RD Curves] The current test suite uses linear interpolation to match quality between the codec being tested and the JPEG baseline. The curve isn't linear, so there is some minor error introduced. This is resolved by switching to RD curves, which don't require quality matching or interpolation. | |||
* [Fixed] Currently we run the Y-SSIM quality score on PNG images, which are using the RGB colorspace. The input and output images (after encode/decode cycle) are available in YUV image format. Evaluating Y-SSIM quality score (SSIM on the Luma channel Y) on YUV image makes more sense than computing it over RGB colorspace. Solution is to make quality metric programs take YUV input. | |||
* [Fixed] Currently, the matlab implementation of Y-SSIM (ssim.m) down-scales the images to a normalized dimension of 256. The downscale transformation will smooth out the image feature details and can bump up SSIM quality score evaluated on the Luma channel. | |||
* Investigate the following feedback from Hacker News. | |||
** https://news.ycombinator.com/item?id=6581827 | |||
Quality Tests to Port to C | |||
* IW-SSIM | |||
Data Output | |||
* [Fixed] Output RD curve result data to format that is easily human and machine readable (e.g. CSV) (this currently exists for several still image formats: [https://git.xiph.org/?p=daala.git;a=blob;f=tools/rd_collect.sh daala/tools/rd_collect.sh]) | |||
Graphing Capabilities | |||
* [Fixed] Add ability to create a graph with one or more sets of RD curve results. (this currently exists using gnuplot: [https://git.xiph.org/?p=daala.git;a=blob;f=tools/rd_plot.sh daala/tools/rd_plot.sh]) | |||