Documentation
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Overview ¶
Package jpegtest builds hostile JPEG fixtures for the tests of the framework's image-adjacent packages (framework/image and framework/file). Tests only: nothing outside a _test.go file imports it, so it never links into a binary.
Index ¶
Constants ¶
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Variables ¶
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Functions ¶
func Progressive ¶
Progressive returns a valid progressive JPEG of w×h pixels with comps components (1 or 3, each sampled 1×1) and scans AC scans, each the ScanBomb scan over one component in turn. A few hundred bytes buy the decoder's whole-frame coefficient buffer: image/jpeg keeps 256 bytes per block of every component a scan names, so a 3-component 8192×8192 frame allocates 768 MB of coefficients before its pixels.
func ScanBomb ¶
ScanBomb returns a valid grayscale progressive JPEG of w×h pixels made of scans copies of one AC scan. Each scan is a single end-of-band run code repeated to cover every block, so it costs about ten bytes per 330,000 blocks while the decoder walks every block of the frame again: decode CPU grows with scans × pixels and the file with scans alone. w and h must each fit in 16 bits.
Types ¶
This section is empty.
Source Files