1/*
2 * Copyright 2013 Google Inc.
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7
8#include "SkImageEncoder.h"
9#include "SkBitmap.h"
10#include "SkColorPriv.h"
11#include "SkStream.h"
12#include "SkTemplates.h"
13
14class SkARGBImageEncoder : public SkImageEncoder {
15protected:
16    virtual bool onEncode(SkWStream* stream, const SkBitmap& bm, int quality) SK_OVERRIDE;
17
18private:
19    typedef SkImageEncoder INHERITED;
20};
21
22typedef void (*ScanlineImporter)(const uint8_t* in, uint8_t* argb, int width,
23                                 const SkPMColor* SK_RESTRICT ctable);
24
25static void ARGB_8888_To_ARGB(const uint8_t* in, uint8_t* argb, int width, const SkPMColor*) {
26  const uint32_t* SK_RESTRICT src = (const uint32_t*)in;
27  for (int i = 0; i < width; ++i) {
28      const uint32_t c = *src++;
29      argb[0] = SkGetPackedA32(c);
30      argb[1] = SkGetPackedR32(c);
31      argb[2] = SkGetPackedG32(c);
32      argb[3] = SkGetPackedB32(c);
33      argb += 4;
34  }
35}
36
37static void RGB_565_To_ARGB(const uint8_t* in, uint8_t* argb, int width, const SkPMColor*) {
38  const uint16_t* SK_RESTRICT src = (const uint16_t*)in;
39  for (int i = 0; i < width; ++i) {
40      const uint16_t c = *src++;
41      argb[0] = 0xFF;
42      argb[1] = SkPacked16ToR32(c);
43      argb[2] = SkPacked16ToG32(c);
44      argb[3] = SkPacked16ToB32(c);
45      argb += 4;
46  }
47}
48
49static void ARGB_4444_To_ARGB(const uint8_t* in, uint8_t* argb, int width, const SkPMColor*) {
50  const SkPMColor16* SK_RESTRICT src = (const SkPMColor16*)in;
51  for (int i = 0; i < width; ++i) {
52      const SkPMColor16 c = *src++;
53      argb[0] = SkPacked4444ToA32(c);
54      argb[1] = SkPacked4444ToR32(c);
55      argb[2] = SkPacked4444ToG32(c);
56      argb[3] = SkPacked4444ToB32(c);
57      argb += 4;
58  }
59}
60
61static void Index8_To_ARGB(const uint8_t* in, uint8_t* argb, int width,
62                           const SkPMColor* SK_RESTRICT ctable) {
63  const uint8_t* SK_RESTRICT src = (const uint8_t*)in;
64  for (int i = 0; i < width; ++i) {
65      const uint32_t c = ctable[*src++];
66      argb[0] = SkGetPackedA32(c);
67      argb[1] = SkGetPackedR32(c);
68      argb[2] = SkGetPackedG32(c);
69      argb[3] = SkGetPackedB32(c);
70      argb += 4;
71  }
72}
73
74static ScanlineImporter ChooseImporter(const SkBitmap::Config& config) {
75    switch (config) {
76        case SkBitmap::kARGB_8888_Config:
77            return ARGB_8888_To_ARGB;
78        case SkBitmap::kRGB_565_Config:
79            return RGB_565_To_ARGB;
80        case SkBitmap::kARGB_4444_Config:
81            return ARGB_4444_To_ARGB;
82        case SkBitmap::kIndex8_Config:
83            return Index8_To_ARGB;
84        default:
85            return NULL;
86    }
87}
88
89bool SkARGBImageEncoder::onEncode(SkWStream* stream, const SkBitmap& bitmap, int) {
90    const SkBitmap::Config config = bitmap.config();
91    const ScanlineImporter scanline_import = ChooseImporter(config);
92    if (NULL == scanline_import) {
93        return false;
94    }
95
96    SkAutoLockPixels alp(bitmap);
97    const uint8_t* src = (uint8_t*)bitmap.getPixels();
98    if (NULL == bitmap.getPixels()) {
99        return false;
100    }
101
102    SkAutoLockColors ctLocker;
103    const SkPMColor* colors = ctLocker.lockColors(bitmap);
104
105    const int argbStride = bitmap.width() * 4;
106    SkAutoTDeleteArray<uint8_t> ada(new uint8_t[argbStride]);
107    uint8_t* argb = ada.get();
108    for (int y = 0; y < bitmap.height(); ++y) {
109        scanline_import(src + y * bitmap.rowBytes(), argb, bitmap.width(), colors);
110        stream->write(argb, argbStride);
111    }
112
113    return true;
114}
115
116
117///////////////////////////////////////////////////////////////////////////////
118DEFINE_ENCODER_CREATOR(ARGBImageEncoder);
119///////////////////////////////////////////////////////////////////////////////
120