FFmpeg: libavcodec/cdxl.c Source File

FFmpeg

[フレーム]

libavcodec

cdxl.c

Go to the documentation of this file.

1 /*

2 * CDXL video decoder

4 *

5 * This file is part of FFmpeg.

6 *

7 * FFmpeg is free software; you can redistribute it and/or

8 * modify it under the terms of the GNU Lesser General Public

9 * License as published by the Free Software Foundation; either

10 * version 2.1 of the License, or (at your option) any later version.

11 *

12 * FFmpeg is distributed in the hope that it will be useful,

13 * but WITHOUT ANY WARRANTY; without even the implied warranty of

14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU

15 * Lesser General Public License for more details.

16 *

17 * You should have received a copy of the GNU Lesser General Public

18 * License along with FFmpeg; if not, write to the Free Software

19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

20 */

22 #define UNCHECKED_BITSTREAM_READER 1

24 #include "libavutil/intreadwrite.h"

25 #include "libavutil/imgutils.h"

26 #include "avcodec.h"

27 #include "get_bits.h"

28 #include "internal.h"

30 #define BIT_PLANAR 0x00

31 #define CHUNKY 0x20

32 #define BYTE_PLANAR 0x40

33 #define BIT_LINE 0x80

34 #define BYTE_LINE 0xC0

36 typedef struct {

37 AVCodecContext *avctx;

38 AVFrame frame;

39 int bpp;

40 int format;

41 int padded_bits;

42 const uint8_t *palette;

43 int palette_size;

44 const uint8_t *video;

45 int video_size;

46 uint8_t *new_video;

47 int new_video_size;

48 } CDXLVideoContext;

50 static av_cold int cdxl_decode_init(AVCodecContext *avctx)

51 {

52 CDXLVideoContext *c = avctx->priv_data;

54 avcodec_get_frame_defaults(&c->frame);

55 c->new_video_size = 0;

56 c->avctx = avctx;

58 return 0;

59 }

61 static void import_palette(CDXLVideoContext *c, uint32_t *new_palette)

62 {

63 int i;

65 for (i = 0; i < c->palette_size / 2; i++) {

66 unsigned rgb = AV_RB16(&c->palette[i * 2]);

67 unsigned r = ((rgb >> 8) & 0xF) * 0x11;

68 unsigned g = ((rgb >> 4) & 0xF) * 0x11;

69 unsigned b = (rgb & 0xF) * 0x11;

70 AV_WN32(&new_palette[i], (0xFFU << 24) | (r << 16) | (g << 8) | b);

71 }

72 }

74 static void bitplanar2chunky(CDXLVideoContext *c, int linesize, uint8_t *out)

75 {

76 GetBitContext gb;

77 int x, y, plane;

79 init_get_bits(&gb, c->video, c->video_size * 8);

80 for (plane = 0; plane < c->bpp; plane++) {

81 for (y = 0; y < c->avctx->height; y++) {

82 for (x = 0; x < c->avctx->width; x++)

83 out[linesize * y + x] |= get_bits1(&gb) << plane;

84 skip_bits(&gb, c->padded_bits);

85 }

86 }

87 }

89 static void bitline2chunky(CDXLVideoContext *c, int linesize, uint8_t *out)

90 {

91 GetBitContext gb;

92 int x, y, plane;

94 init_get_bits(&gb, c->video, c->video_size * 8);

95 for (y = 0; y < c->avctx->height; y++) {

96 for (plane = 0; plane < c->bpp; plane++) {

97 for (x = 0; x < c->avctx->width; x++)

98 out[linesize * y + x] |= get_bits1(&gb) << plane;

99 skip_bits(&gb, c->padded_bits);

100 }

101 }

102 }

103

104 static void import_format(CDXLVideoContext *c, int linesize, uint8_t *out)

105 {

106 memset(out, 0, linesize * c->avctx->height);

107

108 switch (c->format) {

109 case BIT_PLANAR:

110 bitplanar2chunky(c, linesize, out);

111 break;

112 case BIT_LINE:

113 bitline2chunky(c, linesize, out);

114 break;

115 }

116 }

117

118 static void cdxl_decode_rgb(CDXLVideoContext *c)

119 {

120 uint32_t *new_palette = (uint32_t *)c->frame.data[1];

121

122 import_palette(c, new_palette);

123 import_format(c, c->frame.linesize[0], c->frame.data[0]);

124 }

125

126 static void cdxl_decode_ham6(CDXLVideoContext *c)

127 {

128 AVCodecContext *avctx = c->avctx;

129 uint32_t new_palette[16], r, g, b;

130 uint8_t *ptr, *out, index, op;

131 int x, y;

132

133 ptr = c->new_video;

134 out = c->frame.data[0];

135

136 import_palette(c, new_palette);

137 import_format(c, avctx->width, c->new_video);

138

139 for (y = 0; y < avctx->height; y++) {

140 r = new_palette[0] & 0xFF0000;

141 g = new_palette[0] & 0xFF00;

142 b = new_palette[0] & 0xFF;

143 for (x = 0; x < avctx->width; x++) {

144 index = *ptr++;

145 op = index >> 4;

146 index &= 15;

147 switch (op) {

148 case 0:

149 r = new_palette[index] & 0xFF0000;

150 g = new_palette[index] & 0xFF00;

151 b = new_palette[index] & 0xFF;

152 break;

153 case 1:

154 b = index * 0x11;

155 break;

156 case 2:

157 r = index * 0x11 << 16;

158 break;

159 case 3:

160 g = index * 0x11 << 8;

161 break;

162 }

163 AV_WL24(out + x * 3, r | g | b);

164 }

165 out += c->frame.linesize[0];

166 }

167 }

168

169 static void cdxl_decode_ham8(CDXLVideoContext *c)

170 {

171 AVCodecContext *avctx = c->avctx;

172 uint32_t new_palette[64], r, g, b;

173 uint8_t *ptr, *out, index, op;

174 int x, y;

175

176 ptr = c->new_video;

177 out = c->frame.data[0];

178

179 import_palette(c, new_palette);

180 import_format(c, avctx->width, c->new_video);

181

182 for (y = 0; y < avctx->height; y++) {

183 r = new_palette[0] & 0xFF0000;

184 g = new_palette[0] & 0xFF00;

185 b = new_palette[0] & 0xFF;

186 for (x = 0; x < avctx->width; x++) {

187 index = *ptr++;

188 op = index >> 6;

189 index &= 63;

190 switch (op) {

191 case 0:

192 r = new_palette[index] & 0xFF0000;

193 g = new_palette[index] & 0xFF00;

194 b = new_palette[index] & 0xFF;

195 break;

196 case 1:

197 b = (index << 2) | (b & 3);

198 break;

199 case 2:

200 r = (index << 18) | (r & (3 << 16));

201 break;

202 case 3:

203 g = (index << 10) | (g & (3 << 8));

204 break;

205 }

206 AV_WL24(out + x * 3, r | g | b);

207 }

208 out += c->frame.linesize[0];

209 }

210 }

211

212 static int cdxl_decode_frame(AVCodecContext *avctx, void *data,

213 int *got_frame, AVPacket *pkt)

214 {

215 CDXLVideoContext *c = avctx->priv_data;

216 AVFrame * const p = &c->frame;

217 int ret, w, h, encoding, aligned_width, buf_size = pkt->size;

218 const uint8_t *buf = pkt->data;

219

220 if (buf_size < 32)

221 return AVERROR_INVALIDDATA;

222 encoding = buf[1] & 7;

223 c->format = buf[1] & 0xE0;

224 w = AV_RB16(&buf[14]);

225 h = AV_RB16(&buf[16]);

226 c->bpp = buf[19];

227 c->palette_size = AV_RB16(&buf[20]);

228 c->palette = buf + 32;

229 c->video = c->palette + c->palette_size;

230 c->video_size = buf_size - c->palette_size - 32;

231

232 if (c->palette_size > 512)

233 return AVERROR_INVALIDDATA;

234 if (buf_size < c->palette_size + 32)

235 return AVERROR_INVALIDDATA;

236 if (c->bpp < 1)

237 return AVERROR_INVALIDDATA;

238 if (c->format != BIT_PLANAR && c->format != BIT_LINE) {

239 av_log_ask_for_sample(avctx, "unsupported pixel format: 0x%0x\n", c->format);

240 return AVERROR_PATCHWELCOME;

241 }

242

243 if ((ret = av_image_check_size(w, h, 0, avctx)) < 0)

244 return ret;

245 if (w != avctx->width || h != avctx->height)

246 avcodec_set_dimensions(avctx, w, h);

247

248 aligned_width = FFALIGN(c->avctx->width, 16);

249 c->padded_bits = aligned_width - c->avctx->width;

250 if (c->video_size < aligned_width * avctx->height * c->bpp / 8)

251 return AVERROR_INVALIDDATA;

252 if (!encoding && c->palette_size && c->bpp <= 8) {

253 avctx->pix_fmt = AV_PIX_FMT_PAL8;

254 } else if (encoding == 1 && (c->bpp == 6 || c->bpp == 8)) {

255 if (c->palette_size != (1 << (c->bpp - 1)))

256 return AVERROR_INVALIDDATA;

257 avctx->pix_fmt = AV_PIX_FMT_BGR24;

258 } else {

259 av_log_ask_for_sample(avctx, "unsupported encoding %d and bpp %d\n",

260 encoding, c->bpp);

261 return AVERROR_PATCHWELCOME;

262 }

263

264 if (p->data[0])

265 avctx->release_buffer(avctx, p);

266

267 p->reference = 0;

268 if ((ret = ff_get_buffer(avctx, p)) < 0) {

269 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");

270 return ret;

271 }

272 p->pict_type = AV_PICTURE_TYPE_I;

273

274 if (encoding) {

275 av_fast_padded_malloc(&c->new_video, &c->new_video_size,

276 h * w + FF_INPUT_BUFFER_PADDING_SIZE);

277 if (!c->new_video)

278 return AVERROR(ENOMEM);

279 if (c->bpp == 8)

280 cdxl_decode_ham8(c);

281 else

282 cdxl_decode_ham6(c);

283 } else {

284 cdxl_decode_rgb(c);

285 }

286 *got_frame = 1;

287 *(AVFrame*)data = c->frame;

288

289 return buf_size;

290 }

291

292 static av_cold int cdxl_decode_end(AVCodecContext *avctx)

293 {

294 CDXLVideoContext *c = avctx->priv_data;

295

296 av_free(c->new_video);

297 if (c->frame.data[0])

298 avctx->release_buffer(avctx, &c->frame);

299

300 return 0;

301 }

302

303 AVCodec ff_cdxl_decoder = {

304 .name = "cdxl",

305 .type = AVMEDIA_TYPE_VIDEO,

306 .id = AV_CODEC_ID_CDXL,

307 .priv_data_size = sizeof(CDXLVideoContext),

308 .init = cdxl_decode_init,

309 .close = cdxl_decode_end,

310 .decode = cdxl_decode_frame,

311 .capabilities = CODEC_CAP_DR1,

312 .long_name = NULL_IF_CONFIG_SMALL("Commodore CDXL video"),

313 };

Generated on Sat May 25 2013 03:58:32 for FFmpeg by doxygen 1.8.2