1 | /* |
2 | QImageIO Routines to read/write WebP images. |
3 | |
4 | Copyright (c) 2012,2013 Martin Koller <kollix@aon.at> |
5 | |
6 | This library is free software; you can redistribute it and/or |
7 | modify it under the terms of the GNU Lesser General Public |
8 | License as published by the Free Software Foundation; either |
9 | version 2.1 of the License, or (at your option) version 3, or any |
10 | later version accepted by the membership of KDE e.V. (or its |
11 | successor approved by the membership of KDE e.V.), which shall |
12 | act as a proxy defined in Section 6 of version 3 of the license. |
13 | |
14 | This library is distributed in the hope that it will be useful, |
15 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
16 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
17 | Lesser General Public License for more details. |
18 | |
19 | You should have received a copy of the GNU Lesser General Public |
20 | License along with this library. If not, see <http://www.gnu.org/licenses/>. |
21 | */ |
22 | |
23 | #include <stdlib.h> |
24 | |
25 | #include "webp.h" |
26 | #include <webp/decode.h> |
27 | #include <webp/encode.h> |
28 | |
29 | #include <QImage> |
30 | #include <QVariant> |
31 | |
32 | //--------------------------------------------------------------------- |
33 | |
34 | WebPHandler::WebPHandler() |
35 | : quality(75) |
36 | { |
37 | } |
38 | |
39 | //--------------------------------------------------------------------- |
40 | |
41 | bool WebPHandler::canRead() const |
42 | { |
43 | if (canRead(device())) { |
44 | setFormat("webp" ); |
45 | return true; |
46 | } |
47 | return false; |
48 | } |
49 | |
50 | //--------------------------------------------------------------------- |
51 | |
52 | bool WebPHandler::read(QImage *retImage) |
53 | { |
54 | QByteArray data = device()->readAll(); |
55 | |
56 | WebPBitstreamFeatures features; |
57 | VP8StatusCode ret = WebPGetFeatures(reinterpret_cast<const uint8_t*>(data.constData()), data.size(), &features); |
58 | if ( ret != VP8_STATUS_OK ) { |
59 | return false; |
60 | } |
61 | |
62 | if ( features.has_alpha ) { |
63 | *retImage = QImage(features.width, features.height, QImage::Format_ARGB32); |
64 | } else { |
65 | *retImage = QImage(features.width, features.height, QImage::Format_RGB32); |
66 | } |
67 | |
68 | if ( retImage->isNull() ) { // out of memory |
69 | return false; |
70 | } |
71 | |
72 | #if Q_BYTE_ORDER == Q_BIG_ENDIAN |
73 | if ( WebPDecodeARGBInto(reinterpret_cast<const uint8_t*>(data.constData()), |
74 | data.size(), reinterpret_cast<uint8_t*>(retImage->bits()), |
75 | retImage->byteCount(), retImage->bytesPerLine()) == 0 ) { |
76 | return false; |
77 | } |
78 | #else |
79 | if ( WebPDecodeBGRAInto(reinterpret_cast<const uint8_t*>(data.constData()), |
80 | data.size(), reinterpret_cast<uint8_t*>(retImage->bits()), |
81 | retImage->byteCount(), retImage->bytesPerLine()) == 0 ) { |
82 | return false; |
83 | } |
84 | #endif |
85 | |
86 | return true; |
87 | } |
88 | |
89 | //--------------------------------------------------------------------- |
90 | |
91 | bool WebPHandler::write(const QImage &image) |
92 | { |
93 | // limitation in WebP |
94 | if ( (image.height() > 16383) || (image.height() == 0) || |
95 | (image.width() > 16383) || (image.width() == 0) ) |
96 | return false; |
97 | |
98 | uint8_t *imageData = new uint8_t[image.width() * image.height() * (3 + image.hasAlphaChannel())]; |
99 | |
100 | size_t idx = 0; |
101 | for (int y = 0; y < image.height(); y++) { |
102 | const QRgb *scanline = reinterpret_cast<const QRgb*>(image.constScanLine(y)); |
103 | for (int x = 0; x < image.width(); x++) { |
104 | imageData[idx++] = qRed(scanline[x]); |
105 | imageData[idx++] = qGreen(scanline[x]); |
106 | imageData[idx++] = qBlue(scanline[x]); |
107 | |
108 | if ( image.hasAlphaChannel() ) { |
109 | imageData[idx++] = qAlpha(scanline[x]); |
110 | } |
111 | } |
112 | } |
113 | |
114 | uint8_t *output = 0; |
115 | size_t size; |
116 | if ( image.hasAlphaChannel() ) { |
117 | size = WebPEncodeRGBA(imageData, image.width(), image.height(), image.width() * 4, quality, &output); |
118 | } else { |
119 | size = WebPEncodeRGB(imageData, image.width(), image.height(), image.width() * 4, quality, &output); |
120 | } |
121 | delete [] imageData; |
122 | |
123 | if ( size == 0 ) { |
124 | free(output); |
125 | return false; |
126 | } |
127 | |
128 | device()->write(reinterpret_cast<const char*>(output), size); |
129 | free(output); |
130 | |
131 | return true; |
132 | } |
133 | |
134 | //--------------------------------------------------------------------- |
135 | |
136 | QByteArray WebPHandler::format() const |
137 | { |
138 | return "webp" ; |
139 | } |
140 | |
141 | //--------------------------------------------------------------------- |
142 | |
143 | bool WebPHandler::supportsOption(ImageOption option) const |
144 | { |
145 | return (option == Quality) || (option == Size); |
146 | } |
147 | |
148 | //--------------------------------------------------------------------- |
149 | |
150 | QVariant WebPHandler::option(ImageOption option) const |
151 | { |
152 | switch ( option ) |
153 | { |
154 | case Quality: |
155 | return quality; |
156 | |
157 | case Size: { |
158 | QByteArray data = device()->peek(26); |
159 | |
160 | int width = 0, height = 0; |
161 | |
162 | if ( WebPGetInfo(reinterpret_cast<const uint8_t*>(data.constData()), |
163 | data.size(), &width, &height) == 0 ) |
164 | return QSize(); // header error |
165 | |
166 | return QSize(width, height); |
167 | } |
168 | |
169 | default: return QVariant(); |
170 | } |
171 | } |
172 | |
173 | //--------------------------------------------------------------------- |
174 | |
175 | void WebPHandler::setOption(ImageOption option, const QVariant &value) |
176 | { |
177 | if (option == Quality) |
178 | quality = qBound(0, value.toInt(), 100); |
179 | } |
180 | |
181 | //--------------------------------------------------------------------- |
182 | |
183 | bool WebPHandler::canRead(QIODevice *device) |
184 | { |
185 | if (!device) { |
186 | qWarning("WebPHandler::canRead() called with no device" ); |
187 | return false; |
188 | } |
189 | |
190 | // WebP file header: 4 bytes "RIFF", 4 bytes length, 4 bytes "WEBP" |
191 | QByteArray = device->peek(12); |
192 | |
193 | return (header.size() == 12) && header.startsWith("RIFF" ) && header.endsWith("WEBP" ); |
194 | } |
195 | |
196 | //--------------------------------------------------------------------- |
197 | //--------------------------------------------------------------------- |
198 | |
199 | class WebPPlugin : public QImageIOPlugin |
200 | { |
201 | public: |
202 | QStringList keys() const; |
203 | Capabilities capabilities(QIODevice *device, const QByteArray &format) const; |
204 | QImageIOHandler *create(QIODevice *device, const QByteArray &format = QByteArray()) const; |
205 | }; |
206 | |
207 | //--------------------------------------------------------------------- |
208 | |
209 | QStringList WebPPlugin::keys() const |
210 | { |
211 | return QStringList() << "webp" ; |
212 | } |
213 | |
214 | //--------------------------------------------------------------------- |
215 | |
216 | QImageIOPlugin::Capabilities WebPPlugin::capabilities(QIODevice *device, const QByteArray &format) const |
217 | { |
218 | if (format == "webp" ) |
219 | return Capabilities(CanRead | CanWrite); |
220 | if (!format.isEmpty()) |
221 | return 0; |
222 | if (!device->isOpen()) |
223 | return 0; |
224 | |
225 | Capabilities cap; |
226 | if (device->isReadable() && WebPHandler::canRead(device)) |
227 | cap |= CanRead; |
228 | if (device->isWritable()) |
229 | cap |= CanWrite; |
230 | return cap; |
231 | } |
232 | |
233 | //--------------------------------------------------------------------- |
234 | |
235 | QImageIOHandler *WebPPlugin::create(QIODevice *device, const QByteArray &format) const |
236 | { |
237 | QImageIOHandler *handler = new WebPHandler; |
238 | handler->setDevice(device); |
239 | handler->setFormat(format); |
240 | return handler; |
241 | } |
242 | |
243 | //--------------------------------------------------------------------- |
244 | |
245 | Q_EXPORT_STATIC_PLUGIN(WebPPlugin) |
246 | Q_EXPORT_PLUGIN2(webp, WebPPlugin) |
247 | |