Say when a /Decode array shaped a picture - #32
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A picture and the same picture as another tool EXTRACTS it can be exact complements of each other for a reason that is not a disagreement. /Decode maps the stored samples onto the range the colour space wants; this applies it, as a viewer must, and pdfimages writes the samples as stored. On a one-bit mask a /Decode of [1 0] therefore inverts every pixel. Judged against pdfimages over a corpus of scanned medical pages, 8 of 23 JBIG2 masks differed at exactly 1.0000 — every pixel — and the pages they are on differ from poppler's rendering by a median of 0.0000. Nothing was wrong except the comparison. Of the 248 JBIG2 masks on those first pages, 22 carry /Decode [1 0]. All 22 are soft masks; not one of the 194 stencils carries one. So a picture now says whether an array shaped it, which is the one thing a comparison needs in order to tell that case apart from a real one. 100% statement coverage, go vet and -race clean, nine cross-compile targets.
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A picture and the same picture as another tool extracts it can be exact complements of each other for a reason that is not a disagreement.
/Decodemaps the stored samples onto the range the colour space wants; this applies it, as a viewer must, andpdfimageswrites the samples as stored.On a one-bit mask a
/Decodeof[1 0]therefore inverts every pixel. Judged againstpdfimagesover a corpus of scanned medical pages, 8 of 23 JBIG2 masks differed at exactly 1.0000 — every pixel — and the pages they are on differ from poppler's rendering by a median of 0.0000. Nothing was wrong except the comparison.Of the 248 JBIG2 masks on those first pages, 22 carry
/Decode [1 0]. All 22 are soft masks; not one of the 194 stencils carries one.So a picture now says whether an array shaped it — the one thing a comparison needs in order to tell that case apart from a real one.
100% statement coverage,
go vetand-raceclean, nine cross-compile targets.