FFmpeg: libavcodec/asvdec.c Source File

FFmpeg

[フレーム]

libavcodec

asvdec.c

Go to the documentation of this file.

1 /*

3 *

4 * This file is part of FFmpeg.

5 *

6 * FFmpeg 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) any later version.

10 *

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

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

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

14 * Lesser General Public License for more details.

15 *

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

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

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

19 */

21 /**

22 * @file

23 * ASUS V1/V2 decoder.

24 */

26 #include "libavutil/attributes.h"

27 #include "libavutil/mem.h"

29 #include "asv.h"

30 #include "avcodec.h"

31 #include "blockdsp.h"

32 #include "idctdsp.h"

33 #include "internal.h"

34 #include "mathops.h"

35 #include "mpeg12data.h"

37 #define VLC_BITS 6

38 #define ASV2_LEVEL_VLC_BITS 10

40 static VLC ccp_vlc;

41 static VLC level_vlc;

42 static VLC dc_ccp_vlc;

43 static VLC ac_ccp_vlc;

44 static VLC asv2_level_vlc;

46 static av_cold void init_vlcs(ASV1Context *a)

47 {

48 static int done = 0;

50 if (!done) {

51 done = 1;

53 INIT_VLC_STATIC(&ccp_vlc, VLC_BITS, 17,

54 &ff_asv_ccp_tab[0][1], 2, 1,

55 &ff_asv_ccp_tab[0][0], 2, 1, 64);

56 INIT_VLC_STATIC(&dc_ccp_vlc, VLC_BITS, 8,

57 &ff_asv_dc_ccp_tab[0][1], 2, 1,

58 &ff_asv_dc_ccp_tab[0][0], 2, 1, 64);

59 INIT_VLC_STATIC(&ac_ccp_vlc, VLC_BITS, 16,

60 &ff_asv_ac_ccp_tab[0][1], 2, 1,

61 &ff_asv_ac_ccp_tab[0][0], 2, 1, 64);

62 INIT_VLC_STATIC(&level_vlc, VLC_BITS, 7,

63 &ff_asv_level_tab[0][1], 2, 1,

64 &ff_asv_level_tab[0][0], 2, 1, 64);

65 INIT_VLC_STATIC(&asv2_level_vlc, ASV2_LEVEL_VLC_BITS, 63,

66 &ff_asv2_level_tab[0][1], 2, 1,

67 &ff_asv2_level_tab[0][0], 2, 1, 1024);

68 }

69 }

71 // FIXME write a reversed bitstream reader to avoid the double reverse

72 static inline int asv2_get_bits(GetBitContext *gb, int n)

73 {

74 return ff_reverse[get_bits(gb, n) << (8 - n)];

75 }

77 static inline int asv1_get_level(GetBitContext *gb)

78 {

79 int code = get_vlc2(gb, level_vlc.table, VLC_BITS, 1);

81 if (code == 3)

82 return get_sbits(gb, 8);

83 else

84 return code - 3;

85 }

87 static inline int asv2_get_level(GetBitContext *gb)

88 {

89 int code = get_vlc2(gb, asv2_level_vlc.table, ASV2_LEVEL_VLC_BITS, 1);

91 if (code == 31)

92 return (int8_t) asv2_get_bits(gb, 8);

93 else

94 return code - 31;

95 }

97 static inline int asv1_decode_block(ASV1Context *a, int16_t block[64])

98 {

99 int i;

100

101 block[0] = 8 * get_bits(&a->gb, 8);

102

103 for (i = 0; i < 11; i++) {

104 const int ccp = get_vlc2(&a->gb, ccp_vlc.table, VLC_BITS, 1);

105

106 if (ccp) {

107 if (ccp == 16)

108 break;

109 if (ccp < 0 || i >= 10) {

110 av_log(a->avctx, AV_LOG_ERROR, "coded coeff pattern damaged\n");

111 return AVERROR_INVALIDDATA;

112 }

113

114 if (ccp & 8)

115 block[a->scantable.permutated[4 * i + 0]] = (asv1_get_level(&a->gb) * a->intra_matrix[4 * i + 0]) >> 4;

116 if (ccp & 4)

117 block[a->scantable.permutated[4 * i + 1]] = (asv1_get_level(&a->gb) * a->intra_matrix[4 * i + 1]) >> 4;

118 if (ccp & 2)

119 block[a->scantable.permutated[4 * i + 2]] = (asv1_get_level(&a->gb) * a->intra_matrix[4 * i + 2]) >> 4;

120 if (ccp & 1)

121 block[a->scantable.permutated[4 * i + 3]] = (asv1_get_level(&a->gb) * a->intra_matrix[4 * i + 3]) >> 4;

122 }

123 }

124

125 return 0;

126 }

127

128 static inline int asv2_decode_block(ASV1Context *a, int16_t block[64])

129 {

130 int i, count, ccp;

131

132 count = asv2_get_bits(&a->gb, 4);

133

134 block[0] = 8 * asv2_get_bits(&a->gb, 8);

135

136 ccp = get_vlc2(&a->gb, dc_ccp_vlc.table, VLC_BITS, 1);

137 if (ccp) {

138 if (ccp & 4)

139 block[a->scantable.permutated[1]] = (asv2_get_level(&a->gb) * a->intra_matrix[1]) >> 4;

140 if (ccp & 2)

141 block[a->scantable.permutated[2]] = (asv2_get_level(&a->gb) * a->intra_matrix[2]) >> 4;

142 if (ccp & 1)

143 block[a->scantable.permutated[3]] = (asv2_get_level(&a->gb) * a->intra_matrix[3]) >> 4;

144 }

145

146 for (i = 1; i < count + 1; i++) {

147 const int ccp = get_vlc2(&a->gb, ac_ccp_vlc.table, VLC_BITS, 1);

148

149 if (ccp) {

150 if (ccp & 8)

151 block[a->scantable.permutated[4 * i + 0]] = (asv2_get_level(&a->gb) * a->intra_matrix[4 * i + 0]) >> 4;

152 if (ccp & 4)

153 block[a->scantable.permutated[4 * i + 1]] = (asv2_get_level(&a->gb) * a->intra_matrix[4 * i + 1]) >> 4;

154 if (ccp & 2)

155 block[a->scantable.permutated[4 * i + 2]] = (asv2_get_level(&a->gb) * a->intra_matrix[4 * i + 2]) >> 4;

156 if (ccp & 1)

157 block[a->scantable.permutated[4 * i + 3]] = (asv2_get_level(&a->gb) * a->intra_matrix[4 * i + 3]) >> 4;

158 }

159 }

160

161 return 0;

162 }

163

164 static inline int decode_mb(ASV1Context *a, int16_t block[6][64])

165 {

166 int i;

167

168 a->bdsp.clear_blocks(block[0]);

169

170 if (a->avctx->codec_id == AV_CODEC_ID_ASV1) {

171 for (i = 0; i < 6; i++) {

172 if (asv1_decode_block(a, block[i]) < 0)

173 return -1;

174 }

175 } else {

176 for (i = 0; i < 6; i++) {

177 if (asv2_decode_block(a, block[i]) < 0)

178 return -1;

179 }

180 }

181 return 0;

182 }

183

184 static inline void idct_put(ASV1Context *a, AVFrame *frame, int mb_x, int mb_y)

185 {

186 int16_t(*block)[64] = a->block;

187 int linesize = frame->linesize[0];

188

189 uint8_t *dest_y = frame->data[0] + (mb_y * 16 * linesize) + mb_x * 16;

190 uint8_t *dest_cb = frame->data[1] + (mb_y * 8 * frame->linesize[1]) + mb_x * 8;

191 uint8_t *dest_cr = frame->data[2] + (mb_y * 8 * frame->linesize[2]) + mb_x * 8;

192

193 a->idsp.idct_put(dest_y, linesize, block[0]);

194 a->idsp.idct_put(dest_y + 8, linesize, block[1]);

195 a->idsp.idct_put(dest_y + 8 * linesize, linesize, block[2]);

196 a->idsp.idct_put(dest_y + 8 * linesize + 8, linesize, block[3]);

197

198 if (!(a->avctx->flags & CODEC_FLAG_GRAY)) {

199 a->idsp.idct_put(dest_cb, frame->linesize[1], block[4]);

200 a->idsp.idct_put(dest_cr, frame->linesize[2], block[5]);

201 }

202 }

203

204 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,

205 AVPacket *avpkt)

206 {

207 ASV1Context *const a = avctx->priv_data;

208 const uint8_t *buf = avpkt->data;

209 int buf_size = avpkt->size;

210 AVFrame *const p = data;

211 int mb_x, mb_y, ret;

212

213 if ((ret = ff_get_buffer(avctx, p, 0)) < 0)

214 return ret;

215 p->pict_type = AV_PICTURE_TYPE_I;

216 p->key_frame = 1;

217

218 av_fast_padded_malloc(&a->bitstream_buffer, &a->bitstream_buffer_size,

219 buf_size);

220 if (!a->bitstream_buffer)

221 return AVERROR(ENOMEM);

222

223 if (avctx->codec_id == AV_CODEC_ID_ASV1) {

224 a->bbdsp.bswap_buf((uint32_t *) a->bitstream_buffer,

225 (const uint32_t *) buf, buf_size / 4);

226 } else {

227 int i;

228 for (i = 0; i < buf_size; i++)

229 a->bitstream_buffer[i] = ff_reverse[buf[i]];

230 }

231

232 init_get_bits(&a->gb, a->bitstream_buffer, buf_size * 8);

233

234 for (mb_y = 0; mb_y < a->mb_height2; mb_y++) {

235 for (mb_x = 0; mb_x < a->mb_width2; mb_x++) {

236 if ((ret = decode_mb(a, a->block)) < 0)

237 return ret;

238

239 idct_put(a, p, mb_x, mb_y);

240 }

241 }

242

243 if (a->mb_width2 != a->mb_width) {

244 mb_x = a->mb_width2;

245 for (mb_y = 0; mb_y < a->mb_height2; mb_y++) {

246 if ((ret = decode_mb(a, a->block)) < 0)

247 return ret;

248

249 idct_put(a, p, mb_x, mb_y);

250 }

251 }

252

253 if (a->mb_height2 != a->mb_height) {

254 mb_y = a->mb_height2;

255 for (mb_x = 0; mb_x < a->mb_width; mb_x++) {

256 if ((ret = decode_mb(a, a->block)) < 0)

257 return ret;

258

259 idct_put(a, p, mb_x, mb_y);

260 }

261 }

262

263 *got_frame = 1;

264

265 emms_c();

266

267 return (get_bits_count(&a->gb) + 31) / 32 * 4;

268 }

269

270 static av_cold int decode_init(AVCodecContext *avctx)

271 {

272 ASV1Context *const a = avctx->priv_data;

273 const int scale = avctx->codec_id == AV_CODEC_ID_ASV1 ? 1 : 2;

274 int i;

275

276 if (avctx->extradata_size < 1) {

277 av_log(avctx, AV_LOG_WARNING, "No extradata provided\n");

278 }

279

280 ff_asv_common_init(avctx);

281 ff_blockdsp_init(&a->bdsp, avctx);

282 ff_idctdsp_init(&a->idsp, avctx);

283 init_vlcs(a);

284 ff_init_scantable(a->idsp.idct_permutation, &a->scantable, ff_asv_scantab);

285 avctx->pix_fmt = AV_PIX_FMT_YUV420P;

286

287 if (avctx->extradata_size < 1 || (a->inv_qscale = avctx->extradata[0]) == 0) {

288 av_log(avctx, AV_LOG_ERROR, "illegal qscale 0\n");

289 if (avctx->codec_id == AV_CODEC_ID_ASV1)

290 a->inv_qscale = 6;

291 else

292 a->inv_qscale = 10;

293 }

294

295 for (i = 0; i < 64; i++) {

296 int index = ff_asv_scantab[i];

297

298 a->intra_matrix[i] = 64 * scale * ff_mpeg1_default_intra_matrix[index] /

299 a->inv_qscale;

300 }

301

302 return 0;

303 }

304

305 static av_cold int decode_end(AVCodecContext *avctx)

306 {

307 ASV1Context *const a = avctx->priv_data;

308

309 av_freep(&a->bitstream_buffer);

310 a->bitstream_buffer_size = 0;

311

312 return 0;

313 }

314

315 #if CONFIG_ASV1_DECODER

316 AVCodec ff_asv1_decoder = {

317 .name = "asv1",

318 .long_name = NULL_IF_CONFIG_SMALL("ASUS V1"),

319 .type = AVMEDIA_TYPE_VIDEO,

320 .id = AV_CODEC_ID_ASV1,

321 .priv_data_size = sizeof(ASV1Context),

322 .init = decode_init,

323 .close = decode_end,

324 .decode = decode_frame,

325 .capabilities = CODEC_CAP_DR1,

326 };

327 #endif

328

329 #if CONFIG_ASV2_DECODER

330 AVCodec ff_asv2_decoder = {

331 .name = "asv2",

332 .long_name = NULL_IF_CONFIG_SMALL("ASUS V2"),

333 .type = AVMEDIA_TYPE_VIDEO,

334 .id = AV_CODEC_ID_ASV2,

335 .priv_data_size = sizeof(ASV1Context),

336 .init = decode_init,

337 .close = decode_end,

338 .decode = decode_frame,

339 .capabilities = CODEC_CAP_DR1,

340 };

341 #endif

Generated on Sun Mar 8 2015 02:34:48 for FFmpeg by doxygen 1.8.2