1 /*
2 * Copyright (c) 2010, Google Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions are
6 * met:
7 *
8 * * Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * * Redistributions in binary form must reproduce the above
11 * copyright notice, this list of conditions and the following disclaimer
12 * in the documentation and/or other materials provided with the
13 * distribution.
14 * * Neither the name of Google Inc. nor the names of its
15 * contributors may be used to endorse or promote products derived from
16 * this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30
31 #include "config.h"
32 #include "JPEGImageEncoder.h"
33
34 #include "ImageData.h"
35 #include "IntSize.h"
36 #include "SkBitmap.h"
37 #include "SkColorPriv.h"
38 #include "SkUnPreMultiply.h"
39 extern "C" {
40 #include <stdio.h> // jpeglib.h needs stdio.h FILE
41 #include "jpeglib.h"
42 #include <setjmp.h>
43 }
44
45 namespace WebCore {
46
47 struct JPEGOutputBuffer : public jpeg_destination_mgr {
48 Vector<unsigned char>* output;
49 Vector<unsigned char> buffer;
50 };
51
prepareOutput(j_compress_ptr cinfo)52 static void prepareOutput(j_compress_ptr cinfo)
53 {
54 JPEGOutputBuffer* out = static_cast<JPEGOutputBuffer*>(cinfo->dest);
55 const size_t internalBufferSize = 8192;
56 out->buffer.resize(internalBufferSize);
57 out->next_output_byte = out->buffer.data();
58 out->free_in_buffer = out->buffer.size();
59 }
60
writeOutput(j_compress_ptr cinfo)61 static boolean writeOutput(j_compress_ptr cinfo)
62 {
63 JPEGOutputBuffer* out = static_cast<JPEGOutputBuffer*>(cinfo->dest);
64 out->output->append(out->buffer.data(), out->buffer.size());
65 out->next_output_byte = out->buffer.data();
66 out->free_in_buffer = out->buffer.size();
67 return TRUE;
68 }
69
finishOutput(j_compress_ptr cinfo)70 static void finishOutput(j_compress_ptr cinfo)
71 {
72 JPEGOutputBuffer* out = static_cast<JPEGOutputBuffer*>(cinfo->dest);
73 const size_t size = out->buffer.size() - out->free_in_buffer;
74 out->output->append(out->buffer.data(), size);
75 }
76
handleError(j_common_ptr common)77 static void handleError(j_common_ptr common)
78 {
79 jmp_buf* jumpBufferPtr = static_cast<jmp_buf*>(common->client_data);
80 longjmp(*jumpBufferPtr, -1);
81 }
82
preMultipliedBGRAtoRGB(const void * pixels,unsigned int pixelCount,unsigned char * output)83 static void preMultipliedBGRAtoRGB(const void* pixels, unsigned int pixelCount, unsigned char* output)
84 {
85 const SkPMColor* input = static_cast<const SkPMColor*>(pixels);
86 for (; pixelCount-- > 0; ++input) {
87 *output++ = SkGetPackedR32(*input);
88 *output++ = SkGetPackedG32(*input);
89 *output++ = SkGetPackedB32(*input);
90 }
91 }
92
RGBAtoRGB(const unsigned char * input,unsigned int pixels,unsigned char * output)93 static void RGBAtoRGB(const unsigned char* input, unsigned int pixels, unsigned char* output)
94 {
95 for (; pixels-- > 0; input += 4) {
96 *output++ = input[0];
97 *output++ = input[1];
98 *output++ = input[2];
99 }
100 }
101
encodePixels(const IntSize & inputSize,unsigned char * inputPixels,bool premultiplied,int quality,Vector<unsigned char> * output)102 static bool encodePixels(const IntSize& inputSize, unsigned char* inputPixels,
103 bool premultiplied, int quality, Vector<unsigned char>* output)
104 {
105 IntSize imageSize(inputSize);
106 imageSize.clampNegativeToZero();
107 JPEGOutputBuffer destination;
108 destination.output = output;
109 Vector<JSAMPLE> row;
110
111 jpeg_compress_struct cinfo;
112 jpeg_error_mgr error;
113 cinfo.err = jpeg_std_error(&error);
114 error.error_exit = handleError;
115 jmp_buf jumpBuffer;
116 cinfo.client_data = &jumpBuffer;
117
118 if (setjmp(jumpBuffer)) {
119 jpeg_destroy_compress(&cinfo);
120 return false;
121 }
122
123 jpeg_create_compress(&cinfo);
124 cinfo.dest = &destination;
125 cinfo.dest->init_destination = prepareOutput;
126 cinfo.dest->empty_output_buffer = writeOutput;
127 cinfo.dest->term_destination = finishOutput;
128 cinfo.image_height = imageSize.height();
129 cinfo.image_width = imageSize.width();
130 cinfo.in_color_space = JCS_RGB;
131 cinfo.input_components = 3;
132
133 jpeg_set_defaults(&cinfo);
134 jpeg_set_quality(&cinfo, quality, TRUE);
135 jpeg_start_compress(&cinfo, TRUE);
136
137 unsigned char* pixels = inputPixels;
138 row.resize(cinfo.image_width * cinfo.input_components);
139 while (cinfo.next_scanline < cinfo.image_height) {
140 if (premultiplied)
141 preMultipliedBGRAtoRGB(pixels, cinfo.image_width, row.data());
142 else
143 RGBAtoRGB(pixels, cinfo.image_width, row.data());
144 jpeg_write_scanlines(&cinfo, row.dataSlot(), 1);
145 pixels += cinfo.image_width * 4;
146 }
147
148 jpeg_finish_compress(&cinfo);
149 jpeg_destroy_compress(&cinfo);
150 return true;
151 }
152
encode(const SkBitmap & bitmap,int quality,Vector<unsigned char> * output)153 bool JPEGImageEncoder::encode(const SkBitmap& bitmap, int quality, Vector<unsigned char>* output)
154 {
155 if (bitmap.config() != SkBitmap::kARGB_8888_Config)
156 return false; // Only support ARGB 32 bpp skia bitmaps.
157
158 SkAutoLockPixels bitmapLock(bitmap);
159 IntSize imageSize(bitmap.width(), bitmap.height());
160
161 return encodePixels(imageSize, static_cast<unsigned char *>(bitmap.getPixels()),
162 true, quality, output);
163 }
164
encode(const ImageData & imageData,int quality,Vector<unsigned char> * output)165 bool JPEGImageEncoder::encode(const ImageData& imageData, int quality, Vector<unsigned char>* output)
166 {
167 return encodePixels(imageData.size(), imageData.data()->data()->data(),
168 false, quality, output);
169 }
170
171 } // namespace WebCore
172