xref: /third_party/skia/tools/HashAndEncode.cpp (revision cb93a386)
1// Copyright 2019 Google LLC.
2// Use of this source code is governed by a BSD-style license that can be found in the LICENSE file.
3
4#include "include/core/SkICC.h"
5#include "include/core/SkString.h"
6#include "tools/HashAndEncode.h"
7#include "png.h"
8
9static sk_sp<SkColorSpace> rec2020() {
10    return SkColorSpace::MakeRGB(SkNamedTransferFn::kRec2020, SkNamedGamut::kRec2020);
11}
12
13HashAndEncode::HashAndEncode(const SkBitmap& bitmap) : fSize(bitmap.info().dimensions()) {
14    skcms_AlphaFormat srcAlpha;
15    switch (bitmap.alphaType()) {
16        case kUnknown_SkAlphaType: return;
17
18        case kOpaque_SkAlphaType:
19        case kUnpremul_SkAlphaType: srcAlpha = skcms_AlphaFormat_Unpremul;        break;
20        case kPremul_SkAlphaType:   srcAlpha = skcms_AlphaFormat_PremulAsEncoded; break;
21    }
22
23    skcms_PixelFormat srcFmt;
24    switch (bitmap.colorType()) {
25        case kUnknown_SkColorType:            return;
26
27        case kAlpha_8_SkColorType:            srcFmt = skcms_PixelFormat_A_8;             break;
28        case kRGB_565_SkColorType:            srcFmt = skcms_PixelFormat_BGR_565;         break;
29        case kARGB_4444_SkColorType:          srcFmt = skcms_PixelFormat_ABGR_4444;       break;
30        case kRGBA_8888_SkColorType:          srcFmt = skcms_PixelFormat_RGBA_8888;       break;
31        case kBGRA_8888_SkColorType:          srcFmt = skcms_PixelFormat_BGRA_8888;       break;
32        case kSRGBA_8888_SkColorType:         srcFmt = skcms_PixelFormat_RGBA_8888_sRGB;  break;
33        case kRGBA_1010102_SkColorType:       srcFmt = skcms_PixelFormat_RGBA_1010102;    break;
34        case kBGRA_1010102_SkColorType:       srcFmt = skcms_PixelFormat_BGRA_1010102;    break;
35        case kGray_8_SkColorType:             srcFmt = skcms_PixelFormat_G_8;             break;
36        case kRGBA_F16Norm_SkColorType:       srcFmt = skcms_PixelFormat_RGBA_hhhh;       break;
37        case kRGBA_F16_SkColorType:           srcFmt = skcms_PixelFormat_RGBA_hhhh;       break;
38        case kRGBA_F32_SkColorType:           srcFmt = skcms_PixelFormat_RGBA_ffff;       break;
39        case kR16G16B16A16_unorm_SkColorType: srcFmt = skcms_PixelFormat_RGBA_16161616LE; break;
40
41        case kRGB_888x_SkColorType:           srcFmt = skcms_PixelFormat_RGBA_8888;
42                                              srcAlpha = skcms_AlphaFormat_Opaque;     break;
43        case kRGB_101010x_SkColorType:        srcFmt = skcms_PixelFormat_RGBA_1010102;
44                                              srcAlpha = skcms_AlphaFormat_Opaque;     break;
45        case kBGR_101010x_SkColorType:        srcFmt = skcms_PixelFormat_BGRA_1010102;
46                                              srcAlpha = skcms_AlphaFormat_Opaque;     break;
47
48        case kR8G8_unorm_SkColorType:         return;
49        case kR16G16_unorm_SkColorType:       return;
50        case kR16G16_float_SkColorType:       return;
51        case kA16_unorm_SkColorType:          return;
52        case kA16_float_SkColorType:          return;
53    }
54
55    skcms_ICCProfile srcProfile = *skcms_sRGB_profile();
56    if (auto cs = bitmap.colorSpace()) {
57        cs->toProfile(&srcProfile);
58    }
59
60    // Our common format that can represent anything we draw and encode as a PNG:
61    //   - 16-bit big-endian RGBA
62    //   - unpremul
63    //   - Rec. 2020 gamut and transfer function
64    skcms_PixelFormat dstFmt   = skcms_PixelFormat_RGBA_16161616BE;
65    skcms_AlphaFormat dstAlpha = skcms_AlphaFormat_Unpremul;
66    skcms_ICCProfile dstProfile;
67    rec2020()->toProfile(&dstProfile);
68
69    int N = fSize.width() * fSize.height();
70    fPixels.reset(new uint64_t[N]);
71
72    const void* src = bitmap.getPixels();
73    void* dst = fPixels.get();
74    while (N > 0) {
75        int todo = std::min(N, 1<<27);  // Keep todo*8 <= 1B; skcms requires N*bpp < MAX_INT.
76        if (!skcms_Transform(src, srcFmt, srcAlpha, &srcProfile,
77                             dst, dstFmt, dstAlpha, &dstProfile, todo)) {
78            SkASSERT(false);
79            fPixels.reset(nullptr);
80            break;
81        }
82        src = (char*)src + todo*SkColorTypeBytesPerPixel(bitmap.colorType());
83        dst = (char*)dst + todo*sizeof(uint64_t);
84        N -= todo;
85    }
86}
87
88void HashAndEncode::feedHash(SkWStream* st) const {
89    st->write(&fSize, sizeof(fSize));
90    if (const uint64_t* px = fPixels.get()) {
91        st->write(px, sizeof(*px) * fSize.width() * fSize.height());
92    }
93
94    // N.B. changing salt will change the hash of all images produced by DM,
95    // and will cause tens of thousands of new images to be uploaded to Gold.
96    int salt = 1;
97    st->write(&salt, sizeof(salt));
98}
99
100// NOTE: HashAndEncode uses libpng directly rather than through an abstraction
101// like SkPngEncoder to make sure we get stable, portable results independent
102// of any changes to Skia production encoder.
103
104bool HashAndEncode::encodePNG(SkWStream* st,
105                              const char* md5,
106                              CommandLineFlags::StringArray key,
107                              CommandLineFlags::StringArray properties) const {
108    if (!fPixels) {
109        return false;
110    }
111
112    png_structp png = png_create_write_struct(PNG_LIBPNG_VER_STRING, nullptr, nullptr, nullptr);
113    if (!png) {
114        return false;
115    }
116
117    png_infop info = png_create_info_struct(png);
118    if (!info) {
119        png_destroy_write_struct(&png, &info);
120        return false;
121    }
122    auto write_to_stream = +[](png_structp png, png_bytep ptr, png_size_t len) {
123        auto st = (SkWStream*)png_get_io_ptr(png);
124        if (!st->write(ptr, len)) {
125            png_error(png, "HashAndEncode::encodePNG() failed writing stream");
126        }
127    };
128    png_set_write_fn(png, st, write_to_stream, nullptr);
129
130    SkString description;
131    description.append("Key: ");
132    for (int i = 0; i < key.count(); i++) {
133        description.appendf("%s ", key[i]);
134    }
135    description.append("Properties: ");
136    for (int i = 0; i < properties.count(); i++) {
137        description.appendf("%s ", properties[i]);
138    }
139    description.appendf("MD5: %s", md5);
140
141    png_text text[2];
142    text[0].key  = (png_charp)"Author";
143    text[0].text = (png_charp)"DM unified Rec.2020";
144    text[0].compression = PNG_TEXT_COMPRESSION_NONE;
145    text[1].key  = (png_charp)"Description";
146    text[1].text = (png_charp)description.c_str();
147    text[1].compression = PNG_TEXT_COMPRESSION_NONE;
148    png_set_text(png, info, text, SK_ARRAY_COUNT(text));
149
150    png_set_IHDR(png, info, (png_uint_32)fSize.width()
151                          , (png_uint_32)fSize.height()
152                          , 16/*bits per channel*/
153                          , PNG_COLOR_TYPE_RGB_ALPHA
154                          , PNG_INTERLACE_NONE
155                          , PNG_COMPRESSION_TYPE_DEFAULT
156                          , PNG_FILTER_TYPE_DEFAULT);
157
158    // Fastest encoding and decoding, at slight file size cost is no filtering, compression 1.
159    png_set_filter(png, PNG_FILTER_TYPE_BASE, PNG_FILTER_NONE);
160    png_set_compression_level(png, 1);
161
162    static const sk_sp<SkData> profile =
163        SkWriteICCProfile(SkNamedTransferFn::kRec2020, SkNamedGamut::kRec2020);
164    png_set_iCCP(png, info,
165                 "Rec.2020",
166                 0/*compression type... no idea what options are available here*/,
167                 (png_const_bytep)profile->data(),
168                 (png_uint_32)    profile->size());
169
170    png_write_info(png, info);
171    for (int y = 0; y < fSize.height(); y++) {
172        png_write_row(png, (png_bytep)(fPixels.get() + y*fSize.width()));
173    }
174    png_write_end(png, info);
175
176    png_destroy_write_struct(&png, &info);
177    return true;
178}
179
180