diff options
Diffstat (limited to 'src/pkg/image/png/reader_test.go')
| -rw-r--r-- | src/pkg/image/png/reader_test.go | 20 |
1 files changed, 17 insertions, 3 deletions
diff --git a/src/pkg/image/png/reader_test.go b/src/pkg/image/png/reader_test.go index efa6336d7..bcc1a3db4 100644 --- a/src/pkg/image/png/reader_test.go +++ b/src/pkg/image/png/reader_test.go @@ -28,6 +28,7 @@ var filenames = []string{ "basn3p02", "basn3p04", "basn3p08", + "basn3p08-trns", "basn4a08", "basn4a16", "basn6a08", @@ -98,17 +99,30 @@ func sng(w io.WriteCloser, filename string, png image.Image) { // (the PNG spec section 11.3 says "Ancillary chunks may be ignored by a decoder"). io.WriteString(w, "gAMA {1.0000}\n") - // Write the PLTE (if applicable). + // Write the PLTE and tRNS (if applicable). if cpm != nil { + lastAlpha := -1 io.WriteString(w, "PLTE {\n") - for i := 0; i < len(cpm); i++ { - r, g, b, _ := cpm[i].RGBA() + for i, c := range cpm { + r, g, b, a := c.RGBA() + if a != 0xffff { + lastAlpha = i + } r >>= 8 g >>= 8 b >>= 8 fmt.Fprintf(w, " (%3d,%3d,%3d) # rgb = (0x%02x,0x%02x,0x%02x)\n", r, g, b, r, g, b) } io.WriteString(w, "}\n") + if lastAlpha != -1 { + io.WriteString(w, "tRNS {\n") + for i := 0; i <= lastAlpha; i++ { + _, _, _, a := cpm[i].RGBA() + a >>= 8 + fmt.Fprintf(w, " %d", a) + } + io.WriteString(w, "}\n") + } } // Write the IMAGE. |