1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
|
/*
* Copyright (c) 2010, Google Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following disclaimer
* in the documentation and/or other materials provided with the
* distribution.
* * Neither the name of Google Inc. nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "config.h"
#include "platform/image-encoders/skia/JPEGImageEncoder.h"
#include "SkBitmap.h"
#include "SkColorPriv.h"
#include "platform/geometry/IntSize.h"
#include "platform/graphics/ImageBuffer.h"
extern "C" {
#include <setjmp.h>
#include <stdio.h> // jpeglib.h needs stdio.h FILE
#include "jpeglib.h"
}
namespace WebCore {
struct JPEGOutputBuffer : public jpeg_destination_mgr {
Vector<unsigned char>* output;
Vector<unsigned char> buffer;
};
static void prepareOutput(j_compress_ptr cinfo)
{
JPEGOutputBuffer* out = static_cast<JPEGOutputBuffer*>(cinfo->dest);
const size_t internalBufferSize = 8192;
out->buffer.resize(internalBufferSize);
out->next_output_byte = out->buffer.data();
out->free_in_buffer = out->buffer.size();
}
static boolean writeOutput(j_compress_ptr cinfo)
{
JPEGOutputBuffer* out = static_cast<JPEGOutputBuffer*>(cinfo->dest);
out->output->append(out->buffer.data(), out->buffer.size());
out->next_output_byte = out->buffer.data();
out->free_in_buffer = out->buffer.size();
return TRUE;
}
static void finishOutput(j_compress_ptr cinfo)
{
JPEGOutputBuffer* out = static_cast<JPEGOutputBuffer*>(cinfo->dest);
const size_t size = out->buffer.size() - out->free_in_buffer;
out->output->append(out->buffer.data(), size);
}
static void handleError(j_common_ptr common)
{
jmp_buf* jumpBufferPtr = static_cast<jmp_buf*>(common->client_data);
longjmp(*jumpBufferPtr, -1);
}
static void preMultipliedBGRAtoRGB(const unsigned char* pixels, unsigned pixelCount, unsigned char* output)
{
const SkPMColor* input = reinterpret_cast_ptr<const SkPMColor*>(pixels);
for (; pixelCount-- > 0; ++input) {
*output++ = SkGetPackedR32(*input);
*output++ = SkGetPackedG32(*input);
*output++ = SkGetPackedB32(*input);
}
}
static void RGBAtoRGB(const unsigned char* pixels, unsigned pixelCount, unsigned char* output)
{
for (; pixelCount-- > 0; pixels += 4) {
// Do source-over composition on black.
unsigned char alpha = pixels[3];
if (alpha != 255) {
*output++ = SkMulDiv255Round(pixels[0], alpha);
*output++ = SkMulDiv255Round(pixels[1], alpha);
*output++ = SkMulDiv255Round(pixels[2], alpha);
} else {
*output++ = pixels[0];
*output++ = pixels[1];
*output++ = pixels[2];
}
}
}
static void disableSubsamplingForHighQuality(jpeg_compress_struct* cinfo, int quality)
{
if (quality < 100)
return;
for (int i = 0; i < MAX_COMPONENTS; ++i) {
cinfo->comp_info[i].h_samp_factor = 1;
cinfo->comp_info[i].v_samp_factor = 1;
}
}
static bool encodePixels(IntSize imageSize, unsigned char* inputPixels, bool premultiplied, int quality, Vector<unsigned char>* output)
{
JPEGOutputBuffer destination;
destination.output = output;
Vector<JSAMPLE> row;
jpeg_compress_struct cinfo;
jpeg_error_mgr error;
cinfo.err = jpeg_std_error(&error);
error.error_exit = handleError;
jmp_buf jumpBuffer;
cinfo.client_data = &jumpBuffer;
if (setjmp(jumpBuffer)) {
jpeg_destroy_compress(&cinfo);
return false;
}
jpeg_create_compress(&cinfo);
cinfo.dest = &destination;
cinfo.dest->init_destination = prepareOutput;
cinfo.dest->empty_output_buffer = writeOutput;
cinfo.dest->term_destination = finishOutput;
imageSize.clampNegativeToZero();
cinfo.image_height = imageSize.height();
cinfo.image_width = imageSize.width();
#if defined(JCS_EXTENSIONS)
if (premultiplied) {
cinfo.in_color_space = SK_B32_SHIFT ? JCS_EXT_RGBX : JCS_EXT_BGRX;
cinfo.input_components = 4;
jpeg_set_defaults(&cinfo);
jpeg_set_quality(&cinfo, quality, TRUE);
disableSubsamplingForHighQuality(&cinfo, quality);
jpeg_start_compress(&cinfo, TRUE);
unsigned char* pixels = inputPixels;
const size_t pixelRowStride = cinfo.image_width * 4;
while (cinfo.next_scanline < cinfo.image_height) {
jpeg_write_scanlines(&cinfo, &pixels, 1);
pixels += pixelRowStride;
}
jpeg_finish_compress(&cinfo);
jpeg_destroy_compress(&cinfo);
return true;
}
#endif
cinfo.in_color_space = JCS_RGB;
cinfo.input_components = 3;
void (*extractRowRGB)(const unsigned char*, unsigned, unsigned char* output);
extractRowRGB = &RGBAtoRGB;
if (premultiplied)
extractRowRGB = &preMultipliedBGRAtoRGB;
jpeg_set_defaults(&cinfo);
jpeg_set_quality(&cinfo, quality, TRUE);
disableSubsamplingForHighQuality(&cinfo, quality);
jpeg_start_compress(&cinfo, TRUE);
unsigned char* pixels = inputPixels;
row.resize(cinfo.image_width * cinfo.input_components);
const size_t pixelRowStride = cinfo.image_width * 4;
while (cinfo.next_scanline < cinfo.image_height) {
JSAMPLE* rowData = row.data();
extractRowRGB(pixels, cinfo.image_width, rowData);
jpeg_write_scanlines(&cinfo, &rowData, 1);
pixels += pixelRowStride;
}
jpeg_finish_compress(&cinfo);
jpeg_destroy_compress(&cinfo);
return true;
}
bool JPEGImageEncoder::encode(const SkBitmap& bitmap, int quality, Vector<unsigned char>* output)
{
SkAutoLockPixels bitmapLock(bitmap);
if (bitmap.colorType() != kPMColor_SkColorType || !bitmap.getPixels())
return false; // Only support 32 bit/pixel skia bitmaps.
return encodePixels(IntSize(bitmap.width(), bitmap.height()), static_cast<unsigned char *>(bitmap.getPixels()), true, quality, output);
}
bool JPEGImageEncoder::encode(const ImageDataBuffer& imageData, int quality, Vector<unsigned char>* output)
{
return encodePixels(imageData.size(), imageData.data(), false, quality, output);
}
} // namespace WebCore
|
