FFmpeg: libavcodec/rawdec.c Source File

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libavcodec

rawdec.c

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1 /*

2 * Raw 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 /**

23 * @file

24 * Raw Video Decoder

25 */

27 #include "avcodec.h"

28 #include "bswapdsp.h"

29 #include "get_bits.h"

30 #include "internal.h"

31 #include "raw.h"

32 #include "libavutil/avassert.h"

33 #include "libavutil/buffer.h"

34 #include "libavutil/common.h"

35 #include "libavutil/intreadwrite.h"

36 #include "libavutil/imgutils.h"

37 #include "libavutil/opt.h"

39 typedef struct RawVideoContext {

40 AVClass *av_class;

41 AVBufferRef *palette;

42 int frame_size; /* size of the frame in bytes */

43 int flip;

44 int is_2_4_bpp; // 2 or 4 bpp raw in avi/mov

45 int is_yuv2;

46 int is_lt_16bpp; // 16bpp pixfmt and bits_per_coded_sample < 16

47 int tff;

49 BswapDSPContext bbdsp;

50 void *bitstream_buf;

51 unsigned int bitstream_buf_size;

52 } RawVideoContext;

54 static const AVOption options[]={

55 {"top", "top field first", offsetof(RawVideoContext, tff), AV_OPT_TYPE_INT, {.i64 = -1}, -1, 1, AV_OPT_FLAG_DECODING_PARAM|AV_OPT_FLAG_VIDEO_PARAM},

56 {NULL}

57 };

59 static const AVClass rawdec_class = {

60 .class_name = "rawdec",

61 .option = options,

62 .version = LIBAVUTIL_VERSION_INT,

63 };

65 static av_cold int raw_init_decoder(AVCodecContext *avctx)

66 {

67 RawVideoContext *context = avctx->priv_data;

68 const AVPixFmtDescriptor *desc;

70 ff_bswapdsp_init(&context->bbdsp);

72 if ( avctx->codec_tag == MKTAG('r','a','w',' ')

73 || avctx->codec_tag == MKTAG('N','O','1','6'))

74 avctx->pix_fmt = avpriv_find_pix_fmt(avpriv_pix_fmt_bps_mov,

75 avctx->bits_per_coded_sample);

76 else if (avctx->codec_tag == MKTAG('W', 'R', 'A', 'W'))

77 avctx->pix_fmt = avpriv_find_pix_fmt(avpriv_pix_fmt_bps_avi,

78 avctx->bits_per_coded_sample);

79 else if (avctx->codec_tag && (avctx->codec_tag & 0xFFFFFF) != MKTAG('B','I','T', 0))

80 avctx->pix_fmt = avpriv_find_pix_fmt(ff_raw_pix_fmt_tags, avctx->codec_tag);

81 else if (avctx->pix_fmt == AV_PIX_FMT_NONE && avctx->bits_per_coded_sample)

82 avctx->pix_fmt = avpriv_find_pix_fmt(avpriv_pix_fmt_bps_avi,

83 avctx->bits_per_coded_sample);

85 desc = av_pix_fmt_desc_get(avctx->pix_fmt);

86 if (!desc) {

87 av_log(avctx, AV_LOG_ERROR, "Invalid pixel format.\n");

88 return AVERROR(EINVAL);

89 }

91 if (desc->flags & (AV_PIX_FMT_FLAG_PAL | AV_PIX_FMT_FLAG_PSEUDOPAL)) {

92 context->palette = av_buffer_alloc(AVPALETTE_SIZE);

93 if (!context->palette)

94 return AVERROR(ENOMEM);

95 if (desc->flags & AV_PIX_FMT_FLAG_PSEUDOPAL)

96 avpriv_set_systematic_pal2((uint32_t*)context->palette->data, avctx->pix_fmt);

97 else

98 memset(context->palette->data, 0, AVPALETTE_SIZE);

99 }

100

101 if ((avctx->extradata_size >= 9 &&

102 !memcmp(avctx->extradata + avctx->extradata_size - 9, "BottomUp", 9)) ||

103 avctx->codec_tag == MKTAG('c','y','u','v') ||

104 avctx->codec_tag == MKTAG(3, 0, 0, 0) ||

105 avctx->codec_tag == MKTAG('W','R','A','W'))

106 context->flip = 1;

107

108 if (avctx->codec_tag == AV_RL32("yuv2") &&

109 avctx->pix_fmt == AV_PIX_FMT_YUYV422)

110 context->is_yuv2 = 1;

111

112 return 0;

113 }

114

115 static void flip(AVCodecContext *avctx, AVPicture *picture)

116 {

117 picture->data[0] += picture->linesize[0] * (avctx->height - 1);

118 picture->linesize[0] *= -1;

119 }

120

121 /*

122 * Scale sample to 16-bit resolution

123 */

124 #define SCALE16(x, bits) (((x) << (16 - (bits))) | ((x) >> (2 * (bits) - 16)))

125

126 /**

127 * Scale buffer to 16 bits per coded sample resolution

128 */

129 #define MKSCALE16(name, r16, w16) \

130 static void name(AVCodecContext *avctx, uint8_t * dst, const uint8_t *buf, int buf_size, int packed) \

131 { \

132 int i; \

133 if (!packed) { \

134 for (i = 0; i + 1 < buf_size; i += 2) \

135 w16(dst + i, SCALE16(r16(buf + i), avctx->bits_per_coded_sample)); \

136 } else { \

137 GetBitContext gb; \

138 init_get_bits(&gb, buf, buf_size * 8); \

139 for (i = 0; i < avctx->width * avctx->height; i++) { \

140 int sample = get_bits(&gb, avctx->bits_per_coded_sample); \

141 w16(dst + i*2, SCALE16(sample, avctx->bits_per_coded_sample)); \

142 } \

143 } \

144 }

145

146 MKSCALE16(scale16be, AV_RB16, AV_WB16)

147 MKSCALE16(scale16le, AV_RL16, AV_WL16)

148

149 static int raw_decode(AVCodecContext *avctx, void *data, int *got_frame,

150 AVPacket *avpkt)

151 {

152 const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(avctx->pix_fmt);

153 RawVideoContext *context = avctx->priv_data;

154 const uint8_t *buf = avpkt->data;

155 int buf_size = avpkt->size;

156 int linesize_align = 4;

157 int res, len;

158 int need_copy;

159

160 AVFrame *frame = data;

161 AVPicture *picture = data;

162

163 if ((avctx->bits_per_coded_sample == 4 || avctx->bits_per_coded_sample == 2) &&

164 avctx->pix_fmt == AV_PIX_FMT_PAL8 &&

165 (!avctx->codec_tag || avctx->codec_tag == MKTAG('r','a','w',' '))) {

166 context->is_2_4_bpp = 1;

167 context->frame_size = avpicture_get_size(avctx->pix_fmt,

168 FFALIGN(avctx->width, 16),

169 avctx->height);

170 } else {

171 context->is_lt_16bpp = av_get_bits_per_pixel(desc) == 16 && avctx->bits_per_coded_sample && avctx->bits_per_coded_sample < 16;

172 context->frame_size = avpicture_get_size(avctx->pix_fmt, avctx->width,

173 avctx->height);

174 }

175 if (context->frame_size < 0)

176 return context->frame_size;

177

178 need_copy = !avpkt->buf || context->is_2_4_bpp || context->is_yuv2 || context->is_lt_16bpp;

179

180 frame->pict_type = AV_PICTURE_TYPE_I;

181 frame->key_frame = 1;

182

183 res = ff_decode_frame_props(avctx, frame);

184 if (res < 0)

185 return res;

186

187 av_frame_set_pkt_pos (frame, avctx->internal->pkt->pos);

188 av_frame_set_pkt_duration(frame, avctx->internal->pkt->duration);

189

190 if (context->tff >= 0) {

191 frame->interlaced_frame = 1;

192 frame->top_field_first = context->tff;

193 }

194

195 if ((res = av_image_check_size(avctx->width, avctx->height, 0, avctx)) < 0)

196 return res;

197

198 if (need_copy)

199 frame->buf[0] = av_buffer_alloc(FFMAX(context->frame_size, buf_size));

200 else

201 frame->buf[0] = av_buffer_ref(avpkt->buf);

202 if (!frame->buf[0])

203 return AVERROR(ENOMEM);

204

205 //2bpp and 4bpp raw in avi and mov (yes this is ugly ...)

206 if (context->is_2_4_bpp) {

207 int i;

208 uint8_t *dst = frame->buf[0]->data;

209 buf_size = context->frame_size - AVPALETTE_SIZE;

210 if (avctx->bits_per_coded_sample == 4) {

211 for (i = 0; 2 * i + 1 < buf_size && i<avpkt->size; i++) {

212 dst[2 * i + 0] = buf[i] >> 4;

213 dst[2 * i + 1] = buf[i] & 15;

214 }

215 linesize_align = 8;

216 } else {

217 av_assert0(avctx->bits_per_coded_sample == 2);

218 for (i = 0; 4 * i + 3 < buf_size && i<avpkt->size; i++) {

219 dst[4 * i + 0] = buf[i] >> 6;

220 dst[4 * i + 1] = buf[i] >> 4 & 3;

221 dst[4 * i + 2] = buf[i] >> 2 & 3;

222 dst[4 * i + 3] = buf[i] & 3;

223 }

224 linesize_align = 16;

225 }

226 buf = dst;

227 } else if (context->is_lt_16bpp) {

228 uint8_t *dst = frame->buf[0]->data;

229 int packed = (avctx->codec_tag & 0xFFFFFF) == MKTAG('B','I','T', 0);

230 int swap = avctx->codec_tag >> 24;

231

232 if (packed && swap) {

233 av_fast_padded_malloc(&context->bitstream_buf, &context->bitstream_buf_size, buf_size);

234 if (!context->bitstream_buf)

235 return AVERROR(ENOMEM);

236 if (swap == 16)

237 context->bbdsp.bswap16_buf(context->bitstream_buf, (const uint16_t*)buf, buf_size / 2);

238 else if (swap == 32)

239 context->bbdsp.bswap_buf(context->bitstream_buf, (const uint32_t*)buf, buf_size / 4);

240 else

241 return AVERROR_INVALIDDATA;

242 buf = context->bitstream_buf;

243 }

244

245 if (desc->flags & AV_PIX_FMT_FLAG_BE)

246 scale16be(avctx, dst, buf, buf_size, packed);

247 else

248 scale16le(avctx, dst, buf, buf_size, packed);

249

250 buf = dst;

251 } else if (need_copy) {

252 memcpy(frame->buf[0]->data, buf, buf_size);

253 buf = frame->buf[0]->data;

254 }

255

256 if (avctx->codec_tag == MKTAG('A', 'V', '1', 'x') ||

257 avctx->codec_tag == MKTAG('A', 'V', 'u', 'p'))

258 buf += buf_size - context->frame_size;

259

260 len = context->frame_size - (avctx->pix_fmt==AV_PIX_FMT_PAL8 ? AVPALETTE_SIZE : 0);

261 if (buf_size < len && (avctx->codec_tag & 0xFFFFFF) != MKTAG('B','I','T', 0)) {

262 av_log(avctx, AV_LOG_ERROR, "Invalid buffer size, packet size %d < expected frame_size %d\n", buf_size, len);

263 av_buffer_unref(&frame->buf[0]);

264 return AVERROR(EINVAL);

265 }

266

267 if ((res = avpicture_fill(picture, buf, avctx->pix_fmt,

268 avctx->width, avctx->height)) < 0) {

269 av_buffer_unref(&frame->buf[0]);

270 return res;

271 }

272

273 if (avctx->pix_fmt == AV_PIX_FMT_PAL8) {

274 const uint8_t *pal = av_packet_get_side_data(avpkt, AV_PKT_DATA_PALETTE,

275 NULL);

276

277 if (pal) {

278 av_buffer_unref(&context->palette);

279 context->palette = av_buffer_alloc(AVPALETTE_SIZE);

280 if (!context->palette) {

281 av_buffer_unref(&frame->buf[0]);

282 return AVERROR(ENOMEM);

283 }

284 memcpy(context->palette->data, pal, AVPALETTE_SIZE);

285 frame->palette_has_changed = 1;

286 }

287 }

288

289 if ((avctx->pix_fmt==AV_PIX_FMT_BGR24 ||

290 avctx->pix_fmt==AV_PIX_FMT_GRAY8 ||

291 avctx->pix_fmt==AV_PIX_FMT_RGB555LE ||

292 avctx->pix_fmt==AV_PIX_FMT_RGB555BE ||

293 avctx->pix_fmt==AV_PIX_FMT_RGB565LE ||

294 avctx->pix_fmt==AV_PIX_FMT_MONOWHITE ||

295 avctx->pix_fmt==AV_PIX_FMT_PAL8) &&

296 FFALIGN(frame->linesize[0], linesize_align) * avctx->height <= buf_size)

297 frame->linesize[0] = FFALIGN(frame->linesize[0], linesize_align);

298

299 if (avctx->pix_fmt == AV_PIX_FMT_NV12 && avctx->codec_tag == MKTAG('N', 'V', '1', '2') &&

300 FFALIGN(frame->linesize[0], linesize_align) * avctx->height +

301 FFALIGN(frame->linesize[1], linesize_align) * ((avctx->height + 1) / 2) <= buf_size) {

302 int la0 = FFALIGN(frame->linesize[0], linesize_align);

303 frame->data[1] += (la0 - frame->linesize[0]) * avctx->height;

304 frame->linesize[0] = la0;

305 frame->linesize[1] = FFALIGN(frame->linesize[1], linesize_align);

306 }

307

308 if ((avctx->pix_fmt == AV_PIX_FMT_PAL8 && buf_size < context->frame_size) ||

309 (desc->flags & AV_PIX_FMT_FLAG_PSEUDOPAL)) {

310 frame->buf[1] = av_buffer_ref(context->palette);

311 if (!frame->buf[1]) {

312 av_buffer_unref(&frame->buf[0]);

313 return AVERROR(ENOMEM);

314 }

315 frame->data[1] = frame->buf[1]->data;

316 }

317

318 if (avctx->pix_fmt == AV_PIX_FMT_BGR24 &&

319 ((frame->linesize[0] + 3) & ~3) * avctx->height <= buf_size)

320 frame->linesize[0] = (frame->linesize[0] + 3) & ~3;

321

322 if (context->flip)

323 flip(avctx, picture);

324

325 if (avctx->codec_tag == MKTAG('Y', 'V', '1', '2') ||

326 avctx->codec_tag == MKTAG('Y', 'V', '1', '6') ||

327 avctx->codec_tag == MKTAG('Y', 'V', '2', '4') ||

328 avctx->codec_tag == MKTAG('Y', 'V', 'U', '9'))

329 FFSWAP(uint8_t *, picture->data[1], picture->data[2]);

330

331 if (avctx->codec_tag == AV_RL32("I420") && (avctx->width+1)*(avctx->height+1) * 3/2 == buf_size) {

332 picture->data[1] = picture->data[1] + (avctx->width+1)*(avctx->height+1) -avctx->width*avctx->height;

333 picture->data[2] = picture->data[2] + ((avctx->width+1)*(avctx->height+1) -avctx->width*avctx->height)*5/4;

334 }

335

336 if (avctx->codec_tag == AV_RL32("yuv2") &&

337 avctx->pix_fmt == AV_PIX_FMT_YUYV422) {

338 int x, y;

339 uint8_t *line = picture->data[0];

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

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

342 line[2 * x + 1] ^= 0x80;

343 line += picture->linesize[0];

344 }

345 }

346

347 if (avctx->field_order > AV_FIELD_PROGRESSIVE) { /* we have interlaced material flagged in container */

348 frame->interlaced_frame = 1;

349 if (avctx->field_order == AV_FIELD_TT || avctx->field_order == AV_FIELD_TB)

350 frame->top_field_first = 1;

351 }

352

353 *got_frame = 1;

354 return buf_size;

355 }

356

357 static av_cold int raw_close_decoder(AVCodecContext *avctx)

358 {

359 RawVideoContext *context = avctx->priv_data;

360

361 av_buffer_unref(&context->palette);

362 return 0;

363 }

364

365 AVCodec ff_rawvideo_decoder = {

366 .name = "rawvideo",

367 .long_name = NULL_IF_CONFIG_SMALL("raw video"),

368 .type = AVMEDIA_TYPE_VIDEO,

369 .id = AV_CODEC_ID_RAWVIDEO,

370 .priv_data_size = sizeof(RawVideoContext),

371 .init = raw_init_decoder,

372 .close = raw_close_decoder,

373 .decode = raw_decode,

374 .priv_class = &rawdec_class,

375 .capabilities = CODEC_CAP_PARAM_CHANGE,

376 };

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