FFmpeg: libavcodec/asvdec.c Source File

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libavcodec

asvdec.c

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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 "internal.h"

32 #include "mathops.h"

33 #include "mpeg12data.h"

35 #define VLC_BITS 6

36 #define ASV2_LEVEL_VLC_BITS 10

38 static VLC ccp_vlc;

39 static VLC level_vlc;

40 static VLC dc_ccp_vlc;

41 static VLC ac_ccp_vlc;

42 static VLC asv2_level_vlc;

44 static av_cold void init_vlcs(ASV1Context *a)

45 {

46 static int done = 0;

48 if (!done) {

49 done = 1;

51 INIT_VLC_STATIC(&ccp_vlc, VLC_BITS, 17,

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

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

54 INIT_VLC_STATIC(&dc_ccp_vlc, VLC_BITS, 8,

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

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

57 INIT_VLC_STATIC(&ac_ccp_vlc, VLC_BITS, 16,

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

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

60 INIT_VLC_STATIC(&level_vlc, VLC_BITS, 7,

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

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

63 INIT_VLC_STATIC(&asv2_level_vlc, ASV2_LEVEL_VLC_BITS, 63,

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

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

66 }

67 }

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

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

71 {

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

73 }

75 static inline int asv1_get_level(GetBitContext *gb)

76 {

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

79 if (code == 3)

80 return get_sbits(gb, 8);

81 else

82 return code - 3;

83 }

85 static inline int asv2_get_level(GetBitContext *gb)

86 {

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

89 if (code == 31)

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

91 else

92 return code - 31;

93 }

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

96 {

97 int i;

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

100

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

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

103

104 if (ccp) {

105 if (ccp == 16)

106 break;

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

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

109 return AVERROR_INVALIDDATA;

110 }

111

112 if (ccp & 8)

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

114 if (ccp & 4)

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

116 if (ccp & 2)

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

118 if (ccp & 1)

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

120 }

121 }

122

123 return 0;

124 }

125

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

127 {

128 int i, count, ccp;

129

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

131

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

133

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

135 if (ccp) {

136 if (ccp & 4)

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

138 if (ccp & 2)

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

140 if (ccp & 1)

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

142 }

143

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

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

146

147 if (ccp) {

148 if (ccp & 8)

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

150 if (ccp & 4)

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

152 if (ccp & 2)

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

154 if (ccp & 1)

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

156 }

157 }

158

159 return 0;

160 }

161

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

163 {

164 int i;

165

166 a->dsp.clear_blocks(block[0]);

167

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

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

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

171 return -1;

172 }

173 } else {

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

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

176 return -1;

177 }

178 }

179 return 0;

180 }

181

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

183 {

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

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

186

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

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

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

190

191 a->dsp.idct_put(dest_y , linesize, block[0]);

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

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

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

195

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

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

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

199 }

200 }

201

202 static int decode_frame(AVCodecContext *avctx,

203 void *data, int *got_frame,

204 AVPacket *avpkt)

205 {

206 ASV1Context * const a = avctx->priv_data;

207 const uint8_t *buf = avpkt->data;

208 int buf_size = avpkt->size;

209 AVFrame * const p = data;

210 int mb_x, mb_y, ret;

211

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

213 return ret;

214 p->pict_type = AV_PICTURE_TYPE_I;

215 p->key_frame = 1;

216

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

218 buf_size);

219 if (!a->bitstream_buffer)

220 return AVERROR(ENOMEM);

221

222 if (avctx->codec_id == AV_CODEC_ID_ASV1)

223 a->dsp.bswap_buf((uint32_t*)a->bitstream_buffer, (const uint32_t*)buf, buf_size/4);

224 else {

225 int i;

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

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

228 }

229

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

231

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

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

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

235 return ret;

236

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

238 }

239 }

240

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

242 mb_x = a->mb_width2;

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

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

245 return ret;

246

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

248 }

249 }

250

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

252 mb_y = a->mb_height2;

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

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

255 return ret;

256

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

258 }

259 }

260

261 *got_frame = 1;

262

263 emms_c();

264

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

266 }

267

268 static av_cold int decode_init(AVCodecContext *avctx)

269 {

270 ASV1Context * const a = avctx->priv_data;

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

272 int i;

273

274 if (avctx->extradata_size < 1) {

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

276 }

277

278 ff_asv_common_init(avctx);

279 init_vlcs(a);

280 ff_init_scantable(a->dsp.idct_permutation, &a->scantable, ff_asv_scantab);

281 avctx->pix_fmt = AV_PIX_FMT_YUV420P;

282

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

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

285 if (avctx->codec_id == AV_CODEC_ID_ASV1)

286 a->inv_qscale = 6;

287 else

288 a->inv_qscale = 10;

289 }

290

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

292 int index = ff_asv_scantab[i];

293

294 a->intra_matrix[i] = 64 * scale * ff_mpeg1_default_intra_matrix[index] / a->inv_qscale;

295 }

296

297 return 0;

298 }

299

300 static av_cold int decode_end(AVCodecContext *avctx)

301 {

302 ASV1Context * const a = avctx->priv_data;

303

304 av_freep(&a->bitstream_buffer);

305 a->bitstream_buffer_size = 0;

306

307 return 0;

308 }

309

310 #if CONFIG_ASV1_DECODER

311 AVCodec ff_asv1_decoder = {

312 .name = "asv1",

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

314 .type = AVMEDIA_TYPE_VIDEO,

315 .id = AV_CODEC_ID_ASV1,

316 .priv_data_size = sizeof(ASV1Context),

317 .init = decode_init,

318 .close = decode_end,

319 .decode = decode_frame,

320 .capabilities = CODEC_CAP_DR1,

321 };

322 #endif

323

324 #if CONFIG_ASV2_DECODER

325 AVCodec ff_asv2_decoder = {

326 .name = "asv2",

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

328 .type = AVMEDIA_TYPE_VIDEO,

329 .id = AV_CODEC_ID_ASV2,

330 .priv_data_size = sizeof(ASV1Context),

331 .init = decode_init,

332 .close = decode_end,

333 .decode = decode_frame,

334 .capabilities = CODEC_CAP_DR1,

335 };

336 #endif

337

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