aboutsummaryrefslogtreecommitdiffhomepage
path: root/src/images/SkJpegEncoder.cpp
blob: 1c1fb15e2e1216f6c07489106f4ff1a320de4b75 (plain)
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
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
/*
 * Copyright 2007 The Android Open Source Project
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

#include "SkImageEncoderPriv.h"

#ifdef SK_HAS_JPEG_LIBRARY

#include "SkColorData.h"
#include "SkImageEncoderFns.h"
#include "SkImageInfoPriv.h"
#include "SkJpegEncoder.h"
#include "SkJPEGWriteUtility.h"
#include "SkStream.h"
#include "SkTemplates.h"

#include <stdio.h>

extern "C" {
    #include "jpeglib.h"
    #include "jerror.h"
}

class SkJpegEncoderMgr final : SkNoncopyable {
public:

    /*
     * Create the decode manager
     * Does not take ownership of stream
     */
    static std::unique_ptr<SkJpegEncoderMgr> Make(SkWStream* stream) {
        return std::unique_ptr<SkJpegEncoderMgr>(new SkJpegEncoderMgr(stream));
    }

    bool setParams(const SkImageInfo& srcInfo, const SkJpegEncoder::Options& options);

    jpeg_compress_struct* cinfo() { return &fCInfo; }

    skjpeg_error_mgr* errorMgr() { return &fErrMgr; }

    transform_scanline_proc proc() const { return fProc; }

    ~SkJpegEncoderMgr() {
        jpeg_destroy_compress(&fCInfo);
    }

private:

    SkJpegEncoderMgr(SkWStream* stream)
        : fDstMgr(stream)
        , fProc(nullptr)
    {
        fCInfo.err = jpeg_std_error(&fErrMgr);
        fErrMgr.error_exit = skjpeg_error_exit;
        jpeg_create_compress(&fCInfo);
        fCInfo.dest = &fDstMgr;
    }

    jpeg_compress_struct    fCInfo;
    skjpeg_error_mgr        fErrMgr;
    skjpeg_destination_mgr  fDstMgr;
    transform_scanline_proc fProc;
};

bool SkJpegEncoderMgr::setParams(const SkImageInfo& srcInfo, const SkJpegEncoder::Options& options)
{
    auto chooseProc8888 = [&]() {
        if (kUnpremul_SkAlphaType != srcInfo.alphaType() ||
            SkJpegEncoder::AlphaOption::kIgnore == options.fAlphaOption)
        {
            return (transform_scanline_proc) nullptr;
        }

        return transform_scanline_to_premul_legacy;
    };

    J_COLOR_SPACE jpegColorType = JCS_EXT_RGBA;
    int numComponents = 0;
    switch (srcInfo.colorType()) {
        case kRGBA_8888_SkColorType:
            fProc = chooseProc8888();
            jpegColorType = JCS_EXT_RGBA;
            numComponents = 4;
            break;
        case kBGRA_8888_SkColorType:
            fProc = chooseProc8888();
            jpegColorType = JCS_EXT_BGRA;
            numComponents = 4;
            break;
        case kRGB_565_SkColorType:
            fProc = transform_scanline_565;
            jpegColorType = JCS_RGB;
            numComponents = 3;
            break;
        case kARGB_4444_SkColorType:
            if (SkJpegEncoder::AlphaOption::kBlendOnBlack == options.fAlphaOption) {
                return false;
            }

            fProc = transform_scanline_444;
            jpegColorType = JCS_RGB;
            numComponents = 3;
            break;
        case kGray_8_SkColorType:
            SkASSERT(srcInfo.isOpaque());
            jpegColorType = JCS_GRAYSCALE;
            numComponents = 1;
            break;
        case kRGBA_F16_SkColorType:
            if (!srcInfo.colorSpace()) {
                return false;
            }

            if (kUnpremul_SkAlphaType != srcInfo.alphaType() ||
                SkJpegEncoder::AlphaOption::kIgnore == options.fAlphaOption)
            {
                fProc = transform_scanline_F16_to_8888;
            } else {
                fProc = transform_scanline_F16_to_premul_8888;
            }
            jpegColorType = JCS_EXT_RGBA;
            numComponents = 4;
            break;
        default:
            return false;
    }

    fCInfo.image_width = srcInfo.width();
    fCInfo.image_height = srcInfo.height();
    fCInfo.in_color_space = jpegColorType;
    fCInfo.input_components = numComponents;
    jpeg_set_defaults(&fCInfo);

    if (kGray_8_SkColorType != srcInfo.colorType()) {
        switch (options.fDownsample) {
            case SkJpegEncoder::Downsample::k420:
                SkASSERT(2 == fCInfo.comp_info[0].h_samp_factor);
                SkASSERT(2 == fCInfo.comp_info[0].v_samp_factor);
                SkASSERT(1 == fCInfo.comp_info[1].h_samp_factor);
                SkASSERT(1 == fCInfo.comp_info[1].v_samp_factor);
                SkASSERT(1 == fCInfo.comp_info[2].h_samp_factor);
                SkASSERT(1 == fCInfo.comp_info[2].v_samp_factor);
                break;
            case SkJpegEncoder::Downsample::k422:
                fCInfo.comp_info[0].h_samp_factor = 2;
                fCInfo.comp_info[0].v_samp_factor = 1;
                fCInfo.comp_info[1].h_samp_factor = 1;
                fCInfo.comp_info[1].v_samp_factor = 1;
                fCInfo.comp_info[2].h_samp_factor = 1;
                fCInfo.comp_info[2].v_samp_factor = 1;
                break;
            case SkJpegEncoder::Downsample::k444:
                fCInfo.comp_info[0].h_samp_factor = 1;
                fCInfo.comp_info[0].v_samp_factor = 1;
                fCInfo.comp_info[1].h_samp_factor = 1;
                fCInfo.comp_info[1].v_samp_factor = 1;
                fCInfo.comp_info[2].h_samp_factor = 1;
                fCInfo.comp_info[2].v_samp_factor = 1;
                break;
        }
    }

    // Tells libjpeg-turbo to compute optimal Huffman coding tables
    // for the image.  This improves compression at the cost of
    // slower encode performance.
    fCInfo.optimize_coding = TRUE;
    return true;
}

std::unique_ptr<SkEncoder> SkJpegEncoder::Make(SkWStream* dst, const SkPixmap& src,
                                               const Options& options) {
    if (!SkPixmapIsValid(src)) {
        return nullptr;
    }

    std::unique_ptr<SkJpegEncoderMgr> encoderMgr = SkJpegEncoderMgr::Make(dst);

    skjpeg_error_mgr::AutoPushJmpBuf jmp(encoderMgr->errorMgr());
    if (setjmp(jmp)) {
        return nullptr;
    }

    if (!encoderMgr->setParams(src.info(), options)) {
        return nullptr;
    }

    jpeg_set_quality(encoderMgr->cinfo(), options.fQuality, TRUE);
    jpeg_start_compress(encoderMgr->cinfo(), TRUE);

    sk_sp<SkData> icc = icc_from_color_space(src.info());
    if (icc) {
        // Create a contiguous block of memory with the icc signature followed by the profile.
        sk_sp<SkData> markerData =
                SkData::MakeUninitialized(kICCMarkerHeaderSize + icc->size());
        uint8_t* ptr = (uint8_t*) markerData->writable_data();
        memcpy(ptr, kICCSig, sizeof(kICCSig));
        ptr += sizeof(kICCSig);
        *ptr++ = 1; // This is the first marker.
        *ptr++ = 1; // Out of one total markers.
        memcpy(ptr, icc->data(), icc->size());

        jpeg_write_marker(encoderMgr->cinfo(), kICCMarker, markerData->bytes(), markerData->size());
    }

    return std::unique_ptr<SkJpegEncoder>(new SkJpegEncoder(std::move(encoderMgr), src));
}

SkJpegEncoder::SkJpegEncoder(std::unique_ptr<SkJpegEncoderMgr> encoderMgr, const SkPixmap& src)
    : INHERITED(src, encoderMgr->proc() ? encoderMgr->cinfo()->input_components*src.width() : 0)
    , fEncoderMgr(std::move(encoderMgr))
{}

SkJpegEncoder::~SkJpegEncoder() {}

bool SkJpegEncoder::onEncodeRows(int numRows) {
    skjpeg_error_mgr::AutoPushJmpBuf jmp(fEncoderMgr->errorMgr());
    if (setjmp(jmp)) {
        return false;
    }

    const void* srcRow = fSrc.addr(0, fCurrRow);
    for (int i = 0; i < numRows; i++) {
        JSAMPLE* jpegSrcRow = (JSAMPLE*) srcRow;
        if (fEncoderMgr->proc()) {
            fEncoderMgr->proc()((char*)fStorage.get(), (const char*)srcRow, fSrc.width(),
                                fEncoderMgr->cinfo()->input_components, nullptr);
            jpegSrcRow = fStorage.get();
        }

        jpeg_write_scanlines(fEncoderMgr->cinfo(), &jpegSrcRow, 1);
        srcRow = SkTAddOffset<const void>(srcRow, fSrc.rowBytes());
    }

    fCurrRow += numRows;
    if (fCurrRow == fSrc.height()) {
        jpeg_finish_compress(fEncoderMgr->cinfo());
    }

    return true;
}

bool SkJpegEncoder::Encode(SkWStream* dst, const SkPixmap& src, const Options& options) {
    auto encoder = SkJpegEncoder::Make(dst, src, options);
    return encoder.get() && encoder->encodeRows(src.height());
}

#endif