FFmpeg: libavcodec/dv.c Source File

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libavcodec

dv.c

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1 /*

2 * DV decoder

5 *

6 * DV encoder

8 *

9 * 50 Mbps (DVCPRO50) support

11 *

12 * 100 Mbps (DVCPRO HD) support

13 * Initial code by Daniel Maas <dmaas@maasdigital.com> (funded by BBC R&D)

14 * Final code by Roman Shaposhnik

15 *

16 * Many thanks to Dan Dennedy <dan@dennedy.org> for providing wealth

17 * of DV technical info.

18 *

19 * This file is part of FFmpeg.

20 *

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

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

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

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

25 *

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

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

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

29 * Lesser General Public License for more details.

30 *

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

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

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

34 */

36 /**

37 * @file

38 * DV codec.

39 */

41 #include "libavutil/internal.h"

42 #include "libavutil/pixdesc.h"

44 #include "avcodec.h"

45 #include "dv.h"

46 #include "dvdata.h"

47 #include "get_bits.h"

48 #include "internal.h"

49 #include "put_bits.h"

50 #include "simple_idct.h"

52 /* XXX: also include quantization */

53 RL_VLC_ELEM ff_dv_rl_vlc[1664];

55 static inline void dv_calc_mb_coordinates(const AVDVProfile *d, int chan,

56 int seq, int slot, uint16_t *tbl)

57 {

58 static const uint8_t off[] = { 2, 6, 8, 0, 4 };

59 static const uint8_t shuf1[] = { 36, 18, 54, 0, 72 };

60 static const uint8_t shuf2[] = { 24, 12, 36, 0, 48 };

61 static const uint8_t shuf3[] = { 18, 9, 27, 0, 36 };

63 static const uint8_t l_start[] = { 0, 4, 9, 13, 18, 22, 27, 31, 36, 40 };

64 static const uint8_t l_start_shuffled[] = { 9, 4, 13, 0, 18 };

66 static const uint8_t serpent1[] = {

67 0, 1, 2, 2, 1, 0,

68 0, 1, 2, 2, 1, 0,

69 0, 1, 2, 2, 1, 0,

70 0, 1, 2, 2, 1, 0,

71 0, 1, 2

72 };

73 static const uint8_t serpent2[] = {

74 0, 1, 2, 3, 4, 5, 5, 4, 3, 2, 1, 0,

75 0, 1, 2, 3, 4, 5, 5, 4, 3, 2, 1, 0,

76 0, 1, 2, 3, 4, 5

77 };

79 static const uint8_t remap[][2] = {

80 { 0, 0 }, { 0, 0 }, { 0, 0 }, { 0, 0 }, /* dummy */

81 { 0, 0 }, { 0, 1 }, { 0, 2 }, { 0, 3 }, { 10, 0 },

82 { 10, 1 }, { 10, 2 }, { 10, 3 }, { 20, 0 }, { 20, 1 },

83 { 20, 2 }, { 20, 3 }, { 30, 0 }, { 30, 1 }, { 30, 2 },

84 { 30, 3 }, { 40, 0 }, { 40, 1 }, { 40, 2 }, { 40, 3 },

85 { 50, 0 }, { 50, 1 }, { 50, 2 }, { 50, 3 }, { 60, 0 },

86 { 60, 1 }, { 60, 2 }, { 60, 3 }, { 70, 0 }, { 70, 1 },

87 { 70, 2 }, { 70, 3 }, { 0, 64 }, { 0, 65 }, { 0, 66 },

88 { 10, 64 }, { 10, 65 }, { 10, 66 }, { 20, 64 }, { 20, 65 },

89 { 20, 66 }, { 30, 64 }, { 30, 65 }, { 30, 66 }, { 40, 64 },

90 { 40, 65 }, { 40, 66 }, { 50, 64 }, { 50, 65 }, { 50, 66 },

91 { 60, 64 }, { 60, 65 }, { 60, 66 }, { 70, 64 }, { 70, 65 },

92 { 70, 66 }, { 0, 67 }, { 20, 67 }, { 40, 67 }, { 60, 67 }

93 };

95 int i, k, m;

96 int x, y, blk;

98 for (m = 0; m < 5; m++) {

99 switch (d->width) {

100 case 1440:

101 blk = (chan * 11 + seq) * 27 + slot;

102

103 if (chan == 0 && seq == 11) {

104 x = m * 27 + slot;

105 if (x < 90) {

106 y = 0;

107 } else {

108 x = (x - 90) * 2;

109 y = 67;

110 }

111 } else {

112 i = (4 * chan + blk + off[m]) % 11;

113 k = (blk / 11) % 27;

114

115 x = shuf1[m] + (chan & 1) * 9 + k % 9;

116 y = (i * 3 + k / 9) * 2 + (chan >> 1) + 1;

117 }

118 tbl[m] = (x << 1) | (y << 9);

119 break;

120 case 1280:

121 blk = (chan * 10 + seq) * 27 + slot;

122

123 i = (4 * chan + (seq / 5) + 2 * blk + off[m]) % 10;

124 k = (blk / 5) % 27;

125

126 x = shuf1[m] + (chan & 1) * 9 + k % 9;

127 y = (i * 3 + k / 9) * 2 + (chan >> 1) + 4;

128

129 if (x >= 80) {

130 x = remap[y][0] + ((x - 80) << (y > 59));

131 y = remap[y][1];

132 }

133 tbl[m] = (x << 1) | (y << 9);

134 break;

135 case 960:

136 blk = (chan * 10 + seq) * 27 + slot;

137

138 i = (4 * chan + (seq / 5) + 2 * blk + off[m]) % 10;

139 k = (blk / 5) % 27 + (i & 1) * 3;

140

141 x = shuf2[m] + k % 6 + 6 * (chan & 1);

142 y = l_start[i] + k / 6 + 45 * (chan >> 1);

143 tbl[m] = (x << 1) | (y << 9);

144 break;

145 case 720:

146 switch (d->pix_fmt) {

147 case AV_PIX_FMT_YUV422P:

148 x = shuf3[m] + slot / 3;

149 y = serpent1[slot] +

150 ((((seq + off[m]) % d->difseg_size) << 1) + chan) * 3;

151 tbl[m] = (x << 1) | (y << 8);

152 break;

153 case AV_PIX_FMT_YUV420P:

154 x = shuf3[m] + slot / 3;

155 y = serpent1[slot] +

156 ((seq + off[m]) % d->difseg_size) * 3;

157 tbl[m] = (x << 1) | (y << 9);

158 break;

159 case AV_PIX_FMT_YUV411P:

160 i = (seq + off[m]) % d->difseg_size;

161 k = slot + ((m == 1 || m == 2) ? 3 : 0);

162

163 x = l_start_shuffled[m] + k / 6;

164 y = serpent2[k] + i * 6;

165 if (x > 21)

166 y = y * 2 - i * 6;

167 tbl[m] = (x << 2) | (y << 8);

168 break;

169 }

170 default:

171 break;

172 }

173 }

174 }

175

176 /* quantization quanta by QNO for DV100 */

177 static const uint8_t dv100_qstep[16] = {

178 1, /* QNO = 0 and 1 both have no quantization */

179 1,

180 2, 3, 4, 5, 6, 7, 8, 16, 18, 20, 22, 24, 28, 52

181 };

182

183 static const uint8_t dv_quant_areas[4] = { 6, 21, 43, 64 };

184

185 int ff_dv_init_dynamic_tables(DVVideoContext *ctx, const AVDVProfile *d)

186 {

187 int j, i, c, s, p;

188

189 p = i = 0;

190 for (c = 0; c < d->n_difchan; c++) {

191 for (s = 0; s < d->difseg_size; s++) {

192 p += 6;

193 for (j = 0; j < 27; j++) {

194 p += !(j % 3);

195 if (!(DV_PROFILE_IS_1080i50(d) && c != 0 && s == 11) &&

196 !(DV_PROFILE_IS_720p50(d) && s > 9)) {

197 dv_calc_mb_coordinates(d, c, s, j, &ctx->work_chunks[i].mb_coordinates[0]);

198 ctx->work_chunks[i++].buf_offset = p;

199 }

200 p += 5;

201 }

202 }

203 }

204

205 return 0;

206 }

207

208 av_cold int ff_dvvideo_init(AVCodecContext *avctx)

209 {

210 DVVideoContext *s = avctx->priv_data;

211 static int done = 0;

212 int i, j;

213

214 if (!done) {

215 VLC dv_vlc;

216 uint16_t new_dv_vlc_bits[NB_DV_VLC * 2];

217 uint8_t new_dv_vlc_len[NB_DV_VLC * 2];

218 uint8_t new_dv_vlc_run[NB_DV_VLC * 2];

219 int16_t new_dv_vlc_level[NB_DV_VLC * 2];

220

221 done = 1;

222

223 /* it's faster to include sign bit in a generic VLC parsing scheme */

224 for (i = 0, j = 0; i < NB_DV_VLC; i++, j++) {

225 new_dv_vlc_bits[j] = ff_dv_vlc_bits[i];

226 new_dv_vlc_len[j] = ff_dv_vlc_len[i];

227 new_dv_vlc_run[j] = ff_dv_vlc_run[i];

228 new_dv_vlc_level[j] = ff_dv_vlc_level[i];

229

230 if (ff_dv_vlc_level[i]) {

231 new_dv_vlc_bits[j] <<= 1;

232 new_dv_vlc_len[j]++;

233

234 j++;

235 new_dv_vlc_bits[j] = (ff_dv_vlc_bits[i] << 1) | 1;

236 new_dv_vlc_len[j] = ff_dv_vlc_len[i] + 1;

237 new_dv_vlc_run[j] = ff_dv_vlc_run[i];

238 new_dv_vlc_level[j] = -ff_dv_vlc_level[i];

239 }

240 }

241

242 /* NOTE: as a trick, we use the fact the no codes are unused

243 * to accelerate the parsing of partial codes */

244 init_vlc(&dv_vlc, TEX_VLC_BITS, j, new_dv_vlc_len,

245 1, 1, new_dv_vlc_bits, 2, 2, 0);

246 av_assert1(dv_vlc.table_size == 1664);

247

248 for (i = 0; i < dv_vlc.table_size; i++) {

249 int code = dv_vlc.table[i][0];

250 int len = dv_vlc.table[i][1];

251 int level, run;

252

253 if (len < 0) { // more bits needed

254 run = 0;

255 level = code;

256 } else {

257 run = new_dv_vlc_run[code] + 1;

258 level = new_dv_vlc_level[code];

259 }

260 ff_dv_rl_vlc[i].len = len;

261 ff_dv_rl_vlc[i].level = level;

262 ff_dv_rl_vlc[i].run = run;

263 }

264 ff_free_vlc(&dv_vlc);

265 }

266

267 s->avctx = avctx;

268 avctx->chroma_sample_location = AVCHROMA_LOC_TOPLEFT;

269

270 return 0;

271 }

272

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