libavcodec/dvdec.c

   1 /*
   2  * DV decoder
   3  * Copyright (c) 2002 Fabrice Bellard
   4  * Copyright (c) 2004 Roman Shaposhnik
   5  *
   6  * 50 Mbps (DVCPRO50) support
   7  * Copyright (c) 2006 Daniel Maas <dmaas@maasdigital.com>
   8  *
   9  * 100 Mbps (DVCPRO HD) support
  10  * Initial code by Daniel Maas <dmaas@maasdigital.com> (funded by BBC R&D)
  11  * Final code by Roman Shaposhnik
  12  *
  13  * Many thanks to Dan Dennedy <dan@dennedy.org> for providing wealth
  14  * of DV technical info.
  15  *
  16  * This file is part of Libav.
  17  *
  18  * Libav is free software; you can redistribute it and/or
  19  * modify it under the terms of the GNU Lesser General Public
  20  * License as published by the Free Software Foundation; either
  21  * version 2.1 of the License, or (at your option) any later version.
  22  *
  23  * Libav is distributed in the hope that it will be useful,
  24  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  25  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  26  * Lesser General Public License for more details.
  27  *
  28  * You should have received a copy of the GNU Lesser General Public
  29  * License along with Libav; if not, write to the Free Software
  30  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  31  */
  32
  33 /**
  34  * @file
  35  * DV decoder
  36  */
  37
  38 #include "libavutil/internal.h"
  39 #include "libavutil/pixdesc.h"
  40 #include "avcodec.h"
  41 #include "internal.h"
  42 #include "get_bits.h"
  43 #include "put_bits.h"
  44 #include "simple_idct.h"
  45 #include "dvdata.h"
  46
  47 typedef struct BlockInfo {
  48     const uint32_t *factor_table;
  49     const uint8_t *scan_table;
  50     uint8_t pos; /* position in block */
  51     void (*idct_put)(uint8_t *dest, int line_size, int16_t *block);
  52     uint8_t partial_bit_count;
  53     uint32_t partial_bit_buffer;
  54     int shift_offset;
  55 } BlockInfo;
  56
  57 static const int dv_iweight_bits = 14;
  58
  59 /* decode AC coefficients */
  60 static void dv_decode_ac(GetBitContext *gb, BlockInfo *mb, int16_t *block)
  61 {
  62     int last_index = gb->size_in_bits;
  63     const uint8_t  *scan_table   = mb->scan_table;
  64     const uint32_t *factor_table = mb->factor_table;
  65     int pos               = mb->pos;
  66     int partial_bit_count = mb->partial_bit_count;
  67     int level, run, vlc_len, index;
  68
  69     OPEN_READER(re, gb);
  70     UPDATE_CACHE(re, gb);
  71
  72     /* if we must parse a partial VLC, we do it here */
  73     if (partial_bit_count > 0) {
  74         re_cache = re_cache >> partial_bit_count | mb->partial_bit_buffer;
  75         re_index -= partial_bit_count;
  76         mb->partial_bit_count = 0;
  77     }
  78
  79     /* get the AC coefficients until last_index is reached */
  80     for (;;) {
  81         av_dlog(NULL, "%2d: bits=%04x index=%d\n", pos, SHOW_UBITS(re, gb, 16),
  82                 re_index);
  83         /* our own optimized GET_RL_VLC */
  84         index   = NEG_USR32(re_cache, TEX_VLC_BITS);
  85         vlc_len = ff_dv_rl_vlc[index].len;
  86         if (vlc_len < 0) {
  87             index = NEG_USR32((unsigned)re_cache << TEX_VLC_BITS, -vlc_len) +
  88                     ff_dv_rl_vlc[index].level;
  89             vlc_len = TEX_VLC_BITS - vlc_len;
  90         }
  91         level = ff_dv_rl_vlc[index].level;
  92         run   = ff_dv_rl_vlc[index].run;
  93
  94         /* gotta check if we're still within gb boundaries */
  95         if (re_index + vlc_len > last_index) {
  96             /* should be < 16 bits otherwise a codeword could have been parsed */
  97             mb->partial_bit_count = last_index - re_index;
  98             mb->partial_bit_buffer = re_cache & ~(-1u >> mb->partial_bit_count);
  99             re_index = last_index;
 100             break;
 101         }
 102         re_index += vlc_len;
 103
 104         av_dlog(NULL, "run=%d level=%d\n", run, level);
 105         pos += run;
 106         if (pos >= 64)
 107             break;
 108
 109         level = (level * factor_table[pos] + (1 << (dv_iweight_bits - 1))) >> dv_iweight_bits;
 110         block[scan_table[pos]] = level;
 111
 112         UPDATE_CACHE(re, gb);
 113     }
 114     CLOSE_READER(re, gb);
 115     mb->pos = pos;
 116 }
 117
 118 static inline void bit_copy(PutBitContext *pb, GetBitContext *gb)
 119 {
 120     int bits_left = get_bits_left(gb);
 121     while (bits_left >= MIN_CACHE_BITS) {
 122         put_bits(pb, MIN_CACHE_BITS, get_bits(gb, MIN_CACHE_BITS));
 123         bits_left -= MIN_CACHE_BITS;
 124     }
 125     if (bits_left > 0) {
 126         put_bits(pb, bits_left, get_bits(gb, bits_left));
 127     }
 128 }
 129
 130 /* mb_x and mb_y are in units of 8 pixels */
 131 static int dv_decode_video_segment(AVCodecContext *avctx, void *arg)
 132 {
 133     DVVideoContext *s = avctx->priv_data;
 134     DVwork_chunk *work_chunk = arg;
 135     int quant, dc, dct_mode, class1, j;
 136     int mb_index, mb_x, mb_y, last_index;
 137     int y_stride, linesize;
 138     int16_t *block, *block1;
 139     int c_offset;
 140     uint8_t *y_ptr;
 141     const uint8_t *buf_ptr;
 142     PutBitContext pb, vs_pb;
 143     GetBitContext gb;
 144     BlockInfo mb_data[5 * DV_MAX_BPM], *mb, *mb1;
 145     LOCAL_ALIGNED_16(int16_t, sblock, [5*DV_MAX_BPM], [64]);
 146     LOCAL_ALIGNED_16(uint8_t, mb_bit_buffer, [  80 + FF_INPUT_BUFFER_PADDING_SIZE]); /* allow some slack */
 147     LOCAL_ALIGNED_16(uint8_t, vs_bit_buffer, [5*80 + FF_INPUT_BUFFER_PADDING_SIZE]); /* allow some slack */
 148     const int log2_blocksize = 3;
 149     int is_field_mode[5];
 150
 151     assert((((int)mb_bit_buffer) & 7) == 0);
 152     assert((((int)vs_bit_buffer) & 7) == 0);
 153
 154     memset(sblock, 0, 5*DV_MAX_BPM*sizeof(*sblock));
 155
 156     /* pass 1: read DC and AC coefficients in blocks */
 157     buf_ptr = &s->buf[work_chunk->buf_offset*80];
 158     block1  = &sblock[0][0];
 159     mb1     = mb_data;
 160     init_put_bits(&vs_pb, vs_bit_buffer, 5 * 80);
 161     for (mb_index = 0; mb_index < 5; mb_index++, mb1 += s->sys->bpm, block1 += s->sys->bpm * 64) {
 162         /* skip header */
 163         quant = buf_ptr[3] & 0x0f;
 164         buf_ptr += 4;
 165         init_put_bits(&pb, mb_bit_buffer, 80);
 166         mb    = mb1;
 167         block = block1;
 168         is_field_mode[mb_index] = 0;
 169         for (j = 0; j < s->sys->bpm; j++) {
 170             last_index = s->sys->block_sizes[j];
 171             init_get_bits(&gb, buf_ptr, last_index);
 172
 173             /* get the DC */
 174             dc       = get_sbits(&gb, 9);
 175             dct_mode = get_bits1(&gb);
 176             class1   = get_bits(&gb, 2);
 177             if (DV_PROFILE_IS_HD(s->sys)) {
 178                 mb->idct_put     = s->idct_put[0];
 179                 mb->scan_table   = s->dv_zigzag[0];
 180                 mb->factor_table = &s->sys->idct_factor[(j >= 4)*4*16*64 + class1*16*64 + quant*64];
 181                 is_field_mode[mb_index] |= !j && dct_mode;
 182             } else {
 183                 mb->idct_put     = s->idct_put[dct_mode && log2_blocksize == 3];
 184                 mb->scan_table   = s->dv_zigzag[dct_mode];
 185                 mb->factor_table = &s->sys->idct_factor[(class1 == 3)*2*22*64 + dct_mode*22*64 +
 186                                                         (quant + ff_dv_quant_offset[class1])*64];
 187             }
 188             dc = dc << 2;
 189             /* convert to unsigned because 128 is not added in the
 190                standard IDCT */
 191             dc += 1024;
 192             block[0] = dc;
 193             buf_ptr += last_index >> 3;
 194             mb->pos               = 0;
 195             mb->partial_bit_count = 0;
 196
 197             av_dlog(avctx, "MB block: %d, %d ", mb_index, j);
 198             dv_decode_ac(&gb, mb, block);
 199
 200             /* write the remaining bits in a new buffer only if the
 201                block is finished */
 202             if (mb->pos >= 64)
 203                 bit_copy(&pb, &gb);
 204
 205             block += 64;
 206             mb++;
 207         }
 208
 209         /* pass 2: we can do it just after */
 210         av_dlog(avctx, "***pass 2 size=%d MB#=%d\n", put_bits_count(&pb), mb_index);
 211         block = block1;
 212         mb    = mb1;
 213         init_get_bits(&gb, mb_bit_buffer, put_bits_count(&pb));
 214         put_bits32(&pb, 0); // padding must be zeroed
 215         flush_put_bits(&pb);
 216         for (j = 0; j < s->sys->bpm; j++, block += 64, mb++) {
 217             if (mb->pos < 64 && get_bits_left(&gb) > 0) {
 218                 dv_decode_ac(&gb, mb, block);
 219                 /* if still not finished, no need to parse other blocks */
 220                 if (mb->pos < 64)
 221                     break;
 222             }
 223         }
 224         /* all blocks are finished, so the extra bytes can be used at
 225            the video segment level */
 226         if (j >= s->sys->bpm)
 227             bit_copy(&vs_pb, &gb);
 228     }
 229
 230     /* we need a pass over the whole video segment */
 231     av_dlog(avctx, "***pass 3 size=%d\n", put_bits_count(&vs_pb));
 232     block = &sblock[0][0];
 233     mb    = mb_data;
 234     init_get_bits(&gb, vs_bit_buffer, put_bits_count(&vs_pb));
 235     put_bits32(&vs_pb, 0); // padding must be zeroed
 236     flush_put_bits(&vs_pb);
 237     for (mb_index = 0; mb_index < 5; mb_index++) {
 238         for (j = 0; j < s->sys->bpm; j++) {
 239             if (mb->pos < 64) {
 240                 av_dlog(avctx, "start %d:%d\n", mb_index, j);
 241                 dv_decode_ac(&gb, mb, block);
 242             }
 243             if (mb->pos >= 64 && mb->pos < 127)
 244                 av_log(avctx, AV_LOG_ERROR, "AC EOB marker is absent pos=%d\n", mb->pos);
 245             block += 64;
 246             mb++;
 247         }
 248     }
 249
 250     /* compute idct and place blocks */
 251     block = &sblock[0][0];
 252     mb    = mb_data;
 253     for (mb_index = 0; mb_index < 5; mb_index++) {
 254         dv_calculate_mb_xy(s, work_chunk, mb_index, &mb_x, &mb_y);
 255
 256         /* idct_put'ting luminance */
 257         if ((s->sys->pix_fmt == AV_PIX_FMT_YUV420P) ||
 258             (s->sys->pix_fmt == AV_PIX_FMT_YUV411P && mb_x >= (704 / 8)) ||
 259             (s->sys->height >= 720 && mb_y != 134)) {
 260             y_stride = (s->picture.linesize[0] << ((!is_field_mode[mb_index]) * log2_blocksize));
 261         } else {
 262             y_stride = (2 << log2_blocksize);
 263         }
 264         y_ptr = s->picture.data[0] + ((mb_y * s->picture.linesize[0] + mb_x) << log2_blocksize);
 265         linesize = s->picture.linesize[0] << is_field_mode[mb_index];
 266         mb[0]    .idct_put(y_ptr                                   , linesize, block + 0*64);
 267         if (s->sys->video_stype == 4) { /* SD 422 */
 268             mb[2].idct_put(y_ptr + (1 << log2_blocksize)           , linesize, block + 2*64);
 269         } else {
 270             mb[1].idct_put(y_ptr + (1 << log2_blocksize)           , linesize, block + 1*64);
 271             mb[2].idct_put(y_ptr                         + y_stride, linesize, block + 2*64);
 272             mb[3].idct_put(y_ptr + (1 << log2_blocksize) + y_stride, linesize, block + 3*64);
 273         }
 274         mb += 4;
 275         block += 4*64;
 276
 277         /* idct_put'ting chrominance */
 278         c_offset = (((mb_y >>  (s->sys->pix_fmt == AV_PIX_FMT_YUV420P)) * s->picture.linesize[1] +
 279                      (mb_x >> ((s->sys->pix_fmt == AV_PIX_FMT_YUV411P) ? 2 : 1))) << log2_blocksize);
 280         for (j = 2; j; j--) {
 281             uint8_t *c_ptr = s->picture.data[j] + c_offset;
 282             if (s->sys->pix_fmt == AV_PIX_FMT_YUV411P && mb_x >= (704 / 8)) {
 283                   uint64_t aligned_pixels[64/8];
 284                   uint8_t *pixels = (uint8_t*)aligned_pixels;
 285                   uint8_t *c_ptr1, *ptr1;
 286                   int x, y;
 287                   mb->idct_put(pixels, 8, block);
 288                   for (y = 0; y < (1 << log2_blocksize); y++, c_ptr += s->picture.linesize[j], pixels += 8) {
 289                       ptr1   = pixels + (1 << (log2_blocksize - 1));
 290                       c_ptr1 = c_ptr + (s->picture.linesize[j] << log2_blocksize);
 291                       for (x = 0; x < (1 << (log2_blocksize - 1)); x++) {
 292                           c_ptr[x]  = pixels[x];
 293                           c_ptr1[x] = ptr1[x];
 294                       }
 295                   }
 296                   block += 64; mb++;
 297             } else {
 298                   y_stride = (mb_y == 134) ? (1 << log2_blocksize) :
 299                                              s->picture.linesize[j] << ((!is_field_mode[mb_index]) * log2_blocksize);
 300                   linesize = s->picture.linesize[j] << is_field_mode[mb_index];
 301                   (mb++)->    idct_put(c_ptr           , linesize, block); block += 64;
 302                   if (s->sys->bpm == 8) {
 303                       (mb++)->idct_put(c_ptr + y_stride, linesize, block); block += 64;
 304                   }
 305             }
 306         }
 307     }
 308     return 0;
 309 }
 310
 311 /* NOTE: exactly one frame must be given (120000 bytes for NTSC,
 312    144000 bytes for PAL - or twice those for 50Mbps) */
 313 static int dvvideo_decode_frame(AVCodecContext *avctx,
 314                                  void *data, int *got_frame,
 315                                  AVPacket *avpkt)
 316 {
 317     uint8_t *buf = avpkt->data;
 318     int buf_size = avpkt->size;
 319     DVVideoContext *s = avctx->priv_data;
 320     const uint8_t* vsc_pack;
 321     int apt, is16_9;
 322
 323     s->sys = avpriv_dv_frame_profile(s->sys, buf, buf_size);
 324     if (!s->sys || buf_size < s->sys->frame_size || ff_dv_init_dynamic_tables(s->sys)) {
 325         av_log(avctx, AV_LOG_ERROR, "could not find dv frame profile\n");
 326         return -1; /* NOTE: we only accept several full frames */
 327     }
 328
 329     if (s->picture.data[0])
 330         avctx->release_buffer(avctx, &s->picture);
 331
 332     s->picture.reference = 0;
 333     s->picture.key_frame = 1;
 334     s->picture.pict_type = AV_PICTURE_TYPE_I;
 335     avctx->pix_fmt   = s->sys->pix_fmt;
 336     avctx->time_base = s->sys->time_base;
 337     avcodec_set_dimensions(avctx, s->sys->width, s->sys->height);
 338     if (ff_get_buffer(avctx, &s->picture) < 0) {
 339         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
 340         return -1;
 341     }
 342     s->picture.interlaced_frame = 1;
 343     s->picture.top_field_first  = 0;
 344
 345     s->buf = buf;
 346     avctx->execute(avctx, dv_decode_video_segment, s->sys->work_chunks, NULL,
 347                    dv_work_pool_size(s->sys), sizeof(DVwork_chunk));
 348
 349     emms_c();
 350
 351     /* return image */
 352     *got_frame = 1;
 353     *(AVFrame*)data = s->picture;
 354
 355     /* Determine the codec's sample_aspect ratio from the packet */
 356     vsc_pack = buf + 80*5 + 48 + 5;
 357     if ( *vsc_pack == dv_video_control ) {
 358         apt = buf[4] & 0x07;
 359         is16_9 = (vsc_pack && ((vsc_pack[2] & 0x07) == 0x02 || (!apt && (vsc_pack[2] & 0x07) == 0x07)));
 360         avctx->sample_aspect_ratio = s->sys->sar[is16_9];
 361     }
 362
 363     return s->sys->frame_size;
 364 }
 365
 366 static int dvvideo_close(AVCodecContext *c)
 367 {
 368     DVVideoContext *s = c->priv_data;
 369
 370     if (s->picture.data[0])
 371         c->release_buffer(c, &s->picture);
 372
 373     return 0;
 374 }
 375
 376 AVCodec ff_dvvideo_decoder = {
 377     .name           = "dvvideo",
 378     .type           = AVMEDIA_TYPE_VIDEO,
 379     .id             = AV_CODEC_ID_DVVIDEO,
 380     .priv_data_size = sizeof(DVVideoContext),
 381     .init           = ff_dvvideo_init,
 382     .close          = dvvideo_close,
 383     .decode         = dvvideo_decode_frame,
 384     .capabilities   = CODEC_CAP_DR1 | CODEC_CAP_SLICE_THREADS,
 385     .long_name      = NULL_IF_CONFIG_SMALL("DV (Digital Video)"),
 386 };