delta/go-git.git/src/image, branch dev.typealias github.com: golang/go [release-branch.go1.8] image/png: restore Go 1.7 rejection of transparent gray8 images 2017-04-05T15:26:07+00:00 Russ Cox rsc@golang.org 2017-04-05T15:04:46+00:00 43fa04c23cb147c4988d4f422f98d30685f2256c Go 1.7 and earlier rejected these images with chunkOrderError. Go 1.8 panicked during decoding. Go 1.9 will handle them successfully. Make Go 1.8.1 match Go 1.7 and earlier, to remove the panic without introducing new functionality in a minor release. Fixes #19553. Change-Id: I3c73a27aa3932300326273b6b563cdf606f3ab64 Reviewed-on: https://go-review.googlesource.com/39593 Run-TryBot: Russ Cox <rsc@golang.org> Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org> TryBot-Result: Gobot Gobot <gobot@golang.org> 
Go 1.7 and earlier rejected these images with chunkOrderError.
Go 1.8 panicked during decoding.
Go 1.9 will handle them successfully.

Make Go 1.8.1 match Go 1.7 and earlier, to remove the panic
without introducing new functionality in a minor release.

Fixes #19553.

Change-Id: I3c73a27aa3932300326273b6b563cdf606f3ab64
Reviewed-on: https://go-review.googlesource.com/39593
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
image/png: implement grayscale transparency. 2016-10-28T02:10:13+00:00 Nigel Tao nigeltao@golang.org 2016-10-27T23:26:44+00:00 caba0bd18912109f4d9fa2f4807d6ee4ddd5ffab Change-Id: Ib9309ee499fc51be2662d778430ee30089822e57 Reviewed-on: https://go-review.googlesource.com/32143 Reviewed-by: Rob Pike <r@golang.org> 
Change-Id: Ib9309ee499fc51be2662d778430ee30089822e57
Reviewed-on: https://go-review.googlesource.com/32143
Reviewed-by: Rob Pike <r@golang.org>
image/png: implement truecolor transparency. 2016-10-27T22:27:41+00:00 Nigel Tao nigeltao@golang.org 2016-10-27T05:19:15+00:00 4951c793633a55c5d1e4d94283fa82cff31cee48 Change-Id: I99b9a51db29d514ebaa9c1cfde65c0b5184c0f42 Reviewed-on: https://go-review.googlesource.com/32140 Reviewed-by: Rob Pike <r@golang.org> 
Change-Id: I99b9a51db29d514ebaa9c1cfde65c0b5184c0f42
Reviewed-on: https://go-review.googlesource.com/32140
Reviewed-by: Rob Pike <r@golang.org>
image/png: allow tRNS chunk without a PLTE chunk. 2016-10-27T02:59:31+00:00 Nigel Tao nigeltao@golang.org 2016-10-27T02:36:48+00:00 de4b06559119eac499906aaa4d42046b3beed52d While https://www.w3.org/TR/PNG/#5ChunkOrdering says that tRNS's ordering constraint is "After PLTE; before IDAT", it is legal for a tRNS chunk to occur without a PLTE chunk at all, for greyscale and truecolor transparency as opposed to palette-based transparency. See https://www.w3.org/TR/PNG/#11transinfo Fixes #17511. Change-Id: I047b0b01d78a1cda65e00eeac229bb972cda431d Reviewed-on: https://go-review.googlesource.com/32139 Reviewed-by: Rob Pike <r@golang.org> 
While https://www.w3.org/TR/PNG/#5ChunkOrdering says that tRNS's
ordering constraint is "After PLTE; before IDAT", it is legal for a tRNS
chunk to occur without a PLTE chunk at all, for greyscale and truecolor
transparency as opposed to palette-based transparency. See
https://www.w3.org/TR/PNG/#11transinfo

Fixes #17511.

Change-Id: I047b0b01d78a1cda65e00eeac229bb972cda431d
Reviewed-on: https://go-review.googlesource.com/32139
Reviewed-by: Rob Pike <r@golang.org>
image/color: improve speed of RGBA methods 2016-10-25T07:51:17+00:00 Martin Möhrmann martisch@uos.de 2016-10-18T04:18:39+00:00 2113c9ad0d82b3d1a734c0b5fc0efc9c44a920d5 Apply the optimizations added to color conversion functions in https://go-review.googlesource.com/#/c/21910/ to the RGBA methods. YCbCrToRGBA/0-4 6.32ns ± 3% 6.58ns ± 2% +4.15% (p=0.000 n=20+19) YCbCrToRGBA/128-4 8.02ns ± 2% 5.89ns ± 2% -26.57% (p=0.000 n=20+19) YCbCrToRGBA/255-4 8.06ns ± 2% 6.59ns ± 3% -18.18% (p=0.000 n=20+20) NYCbCrAToRGBA/0-4 8.71ns ± 2% 8.78ns ± 2% +0.86% (p=0.036 n=19+20) NYCbCrAToRGBA/128-4 10.3ns ± 4% 7.9ns ± 2% -23.44% (p=0.000 n=20+20) NYCbCrAToRGBA/255-4 9.64ns ± 2% 8.79ns ± 3% -8.80% (p=0.000 n=20+20) Fixes: #15260 Change-Id: I225efdf74603e8d2b4f063054f7baee7a5029de6 Reviewed-on: https://go-review.googlesource.com/31773 Run-TryBot: Martin Möhrmann <martisch@uos.de> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Nigel Tao <nigeltao@golang.org> 
Apply the optimizations added to color conversion functions in
https://go-review.googlesource.com/#/c/21910/ to the RGBA methods.

YCbCrToRGBA/0-4      6.32ns ± 3%  6.58ns ± 2%   +4.15%  (p=0.000 n=20+19)
YCbCrToRGBA/128-4    8.02ns ± 2%  5.89ns ± 2%  -26.57%  (p=0.000 n=20+19)
YCbCrToRGBA/255-4    8.06ns ± 2%  6.59ns ± 3%  -18.18%  (p=0.000 n=20+20)
NYCbCrAToRGBA/0-4    8.71ns ± 2%  8.78ns ± 2%   +0.86%  (p=0.036 n=19+20)
NYCbCrAToRGBA/128-4  10.3ns ± 4%   7.9ns ± 2%  -23.44%  (p=0.000 n=20+20)
NYCbCrAToRGBA/255-4  9.64ns ± 2%  8.79ns ± 3%   -8.80%  (p=0.000 n=20+20)

Fixes: #15260

Change-Id: I225efdf74603e8d2b4f063054f7baee7a5029de6
Reviewed-on: https://go-review.googlesource.com/31773
Run-TryBot: Martin Möhrmann <martisch@uos.de>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Nigel Tao <nigeltao@golang.org>
image/color: tweak the formula for converting to gray. 2016-10-20T22:27:28+00:00 Nigel Tao nigeltao@golang.org 2016-10-20T05:57:55+00:00 584e3ea2581c858688803d41e207eeaa881a2a85 This makes grayModel and gray16Model in color.go use the exact same formula as RGBToYCbCr in ycbcr.go. They were the same formula in theory, but in practice the color.go versions used a divide by 1000 and the ycbcr.go versions used a (presumably faster) shift by 16. This implies the nice property that converting an image.RGBA to an image.YCbCr and then taking only the Y channel is equivalent to converting an image.RGBA directly to an image.Gray. The difference between the two formulae is non-zero, but small: https://play.golang.org/p/qG7oe-eqHI Updates #16251 Change-Id: I288ecb957fd6eceb9626410bd1a8084d2e4f8198 Reviewed-on: https://go-review.googlesource.com/31538 Reviewed-by: Rob Pike <r@golang.org> 
This makes grayModel and gray16Model in color.go use the exact same
formula as RGBToYCbCr in ycbcr.go. They were the same formula in theory,
but in practice the color.go versions used a divide by 1000 and the
ycbcr.go versions used a (presumably faster) shift by 16.

This implies the nice property that converting an image.RGBA to an
image.YCbCr and then taking only the Y channel is equivalent to
converting an image.RGBA directly to an image.Gray.

The difference between the two formulae is non-zero, but small:
https://play.golang.org/p/qG7oe-eqHI

Updates #16251

Change-Id: I288ecb957fd6eceb9626410bd1a8084d2e4f8198
Reviewed-on: https://go-review.googlesource.com/31538
Reviewed-by: Rob Pike <r@golang.org>
image/gif: check handling of truncated GIF files 2016-10-05T04:28:45+00:00 Jeff R. Allen jra@nella.org 2015-12-05T15:06:05+00:00 d1d798dd15e7abbeab335804bd6dfaec6c016018 All the prefixes of the testGIF produce errors today, but they differ wildly in which errors: some are io.EOF, others are io.ErrUnexpectedEOF, and others are gif-specific. Make them all gif-specific to explain context, and make any complaining about EOF be sure to mention the EOF is unexpected. Fixes #11390. Change-Id: I742c39c88591649276268327ea314e68d1de1845 Reviewed-on: https://go-review.googlesource.com/17493 Run-TryBot: Russ Cox <rsc@golang.org> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org> 
All the prefixes of the testGIF produce errors today,
but they differ wildly in which errors: some are io.EOF,
others are io.ErrUnexpectedEOF, and others are gif-specific.
Make them all gif-specific to explain context, and make
any complaining about EOF be sure to mention the EOF
is unexpected.

Fixes #11390.

Change-Id: I742c39c88591649276268327ea314e68d1de1845
Reviewed-on: https://go-review.googlesource.com/17493
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
image/png: improve compression by skipping filter for paletted images 2016-09-27T14:01:20+00:00 Oliver Tonnhofer olt@bogosoft.com 2016-09-27T13:24:00+00:00 7de7d20e9f14c3a8fb9a3bcf6a36a299c74e9ddd Compression of paletted images is more efficient if they are not filtered. This patch skips filtering for cbP8 images. The improvements are demonstrated at https://github.com/olt/compressbench Fixes #16196 Change-Id: Ie973aad287cacf9057e394bb01cf0e4448a77618 Reviewed-on: https://go-review.googlesource.com/29872 Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org> Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org> TryBot-Result: Gobot Gobot <gobot@golang.org> 
Compression of paletted images is more efficient if they are not filtered.
This patch skips filtering for cbP8 images.
The improvements are demonstrated at https://github.com/olt/compressbench

Fixes #16196

Change-Id: Ie973aad287cacf9057e394bb01cf0e4448a77618
Reviewed-on: https://go-review.googlesource.com/29872
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
image/png: add Encode and Decode examples 2016-09-21T19:47:04+00:00 Suyash dextrous93@gmail.com 2016-09-11T07:17:47+00:00 445f51fb119789e08889abcb8ae54b4eb5029fad partially addresses #16360 Change-Id: I8274825b9ca6aec46294c8513b4795b0eb3062a2 Reviewed-on: https://go-review.googlesource.com/28992 Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org> Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org> TryBot-Result: Gobot Gobot <gobot@golang.org> 
partially addresses #16360

Change-Id: I8274825b9ca6aec46294c8513b4795b0eb3062a2
Reviewed-on: https://go-review.googlesource.com/28992
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
image/draw: add FloydSteinberg Drawer example 2016-09-21T00:08:58+00:00 Brad Fitzpatrick bradfitz@golang.org 2016-09-20T23:43:15+00:00 16f81b617eadc739b9097ce4b7d67e9a00a91c7c Updates #16360 Change-Id: I80b981aa291a8e16d2986d4a2dfd84d3819bf488 Reviewed-on: https://go-review.googlesource.com/29443 Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com> 
Updates #16360

Change-Id: I80b981aa291a8e16d2986d4a2dfd84d3819bf488
Reviewed-on: https://go-review.googlesource.com/29443
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>