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libavcodec/dnxhddec.c

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00001 /*
00002  * VC3/DNxHD decoder.
00003  * Copyright (c) 2007 SmartJog S.A., Baptiste Coudurier <baptiste dot coudurier at smartjog dot com>
00004  * Copyright (c) 2011 MirriAd Ltd
00005  *
00006  * 10 bit support added by MirriAd Ltd, Joseph Artsimovich <joseph@mirriad.com>
00007  *
00008  * This file is part of FFmpeg.
00009  *
00010  * FFmpeg is free software; you can redistribute it and/or
00011  * modify it under the terms of the GNU Lesser General Public
00012  * License as published by the Free Software Foundation; either
00013  * version 2.1 of the License, or (at your option) any later version.
00014  *
00015  * FFmpeg is distributed in the hope that it will be useful,
00016  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00017  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00018  * Lesser General Public License for more details.
00019  *
00020  * You should have received a copy of the GNU Lesser General Public
00021  * License along with FFmpeg; if not, write to the Free Software
00022  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00023  */
00024 
00025 //#define TRACE
00026 //#define DEBUG
00027 
00028 #include "libavutil/imgutils.h"
00029 #include "avcodec.h"
00030 #include "get_bits.h"
00031 #include "dnxhddata.h"
00032 #include "dsputil.h"
00033 #include "thread.h"
00034 
00035 typedef struct DNXHDContext {
00036     AVCodecContext *avctx;
00037     AVFrame picture;
00038     GetBitContext gb;
00039     int cid;                            
00040     unsigned int width, height;
00041     unsigned int mb_width, mb_height;
00042     uint32_t mb_scan_index[68];         /* max for 1080p */
00043     int cur_field;                      
00044     VLC ac_vlc, dc_vlc, run_vlc;
00045     int last_dc[3];
00046     DSPContext dsp;
00047     DECLARE_ALIGNED(16, DCTELEM, blocks)[8][64];
00048     ScanTable scantable;
00049     const CIDEntry *cid_table;
00050     int bit_depth; // 8, 10 or 0 if not initialized at all.
00051     void (*decode_dct_block)(struct DNXHDContext *ctx, DCTELEM *block,
00052                              int n, int qscale);
00053     int last_qscale;
00054     int luma_scale[64];
00055     int chroma_scale[64];
00056 } DNXHDContext;
00057 
00058 #define DNXHD_VLC_BITS 9
00059 #define DNXHD_DC_VLC_BITS 7
00060 
00061 static void dnxhd_decode_dct_block_8(DNXHDContext *ctx, DCTELEM *block, int n, int qscale);
00062 static void dnxhd_decode_dct_block_10(DNXHDContext *ctx, DCTELEM *block, int n, int qscale);
00063 
00064 static av_cold int dnxhd_decode_init(AVCodecContext *avctx)
00065 {
00066     DNXHDContext *ctx = avctx->priv_data;
00067 
00068     ctx->avctx = avctx;
00069     avctx->coded_frame = &ctx->picture;
00070     avcodec_get_frame_defaults(&ctx->picture);
00071     ctx->picture.type = AV_PICTURE_TYPE_I;
00072     ctx->picture.key_frame = 1;
00073     return 0;
00074 }
00075 
00076 static int dnxhd_init_vlc(DNXHDContext *ctx, int cid)
00077 {
00078     if (cid != ctx->cid) {
00079         int index;
00080 
00081         if ((index = ff_dnxhd_get_cid_table(cid)) < 0) {
00082             av_log(ctx->avctx, AV_LOG_ERROR, "unsupported cid %d\n", cid);
00083             return -1;
00084         }
00085         ctx->cid_table = &ff_dnxhd_cid_table[index];
00086 
00087         ff_free_vlc(&ctx->ac_vlc);
00088         ff_free_vlc(&ctx->dc_vlc);
00089         ff_free_vlc(&ctx->run_vlc);
00090 
00091         init_vlc(&ctx->ac_vlc, DNXHD_VLC_BITS, 257,
00092                  ctx->cid_table->ac_bits, 1, 1,
00093                  ctx->cid_table->ac_codes, 2, 2, 0);
00094         init_vlc(&ctx->dc_vlc, DNXHD_DC_VLC_BITS, ctx->bit_depth + 4,
00095                  ctx->cid_table->dc_bits, 1, 1,
00096                  ctx->cid_table->dc_codes, 1, 1, 0);
00097         init_vlc(&ctx->run_vlc, DNXHD_VLC_BITS, 62,
00098                  ctx->cid_table->run_bits, 1, 1,
00099                  ctx->cid_table->run_codes, 2, 2, 0);
00100 
00101         ff_init_scantable(ctx->dsp.idct_permutation, &ctx->scantable, ff_zigzag_direct);
00102         ctx->cid = cid;
00103     }
00104     return 0;
00105 }
00106 
00107 static int dnxhd_decode_header(DNXHDContext *ctx, const uint8_t *buf, int buf_size, int first_field)
00108 {
00109     static const uint8_t header_prefix[] = { 0x00, 0x00, 0x02, 0x80, 0x01 };
00110     int i, cid;
00111 
00112     if (buf_size < 0x280)
00113         return -1;
00114 
00115     if (memcmp(buf, header_prefix, 5)) {
00116         av_log(ctx->avctx, AV_LOG_ERROR, "error in header\n");
00117         return -1;
00118     }
00119     if (buf[5] & 2) { /* interlaced */
00120         ctx->cur_field = buf[5] & 1;
00121         ctx->picture.interlaced_frame = 1;
00122         ctx->picture.top_field_first = first_field ^ ctx->cur_field;
00123         av_log(ctx->avctx, AV_LOG_DEBUG, "interlaced %d, cur field %d\n", buf[5] & 3, ctx->cur_field);
00124     }
00125 
00126     ctx->height = AV_RB16(buf + 0x18);
00127     ctx->width  = AV_RB16(buf + 0x1a);
00128 
00129     av_dlog(ctx->avctx, "width %d, height %d\n", ctx->width, ctx->height);
00130 
00131     if (buf[0x21] & 0x40) {
00132         ctx->avctx->pix_fmt = PIX_FMT_YUV422P10;
00133         ctx->avctx->bits_per_raw_sample = 10;
00134         if (ctx->bit_depth != 10) {
00135             dsputil_init(&ctx->dsp, ctx->avctx);
00136             ctx->bit_depth = 10;
00137             ctx->decode_dct_block = dnxhd_decode_dct_block_10;
00138         }
00139     } else {
00140         ctx->avctx->pix_fmt = PIX_FMT_YUV422P;
00141         ctx->avctx->bits_per_raw_sample = 8;
00142         if (ctx->bit_depth != 8) {
00143             dsputil_init(&ctx->dsp, ctx->avctx);
00144             ctx->bit_depth = 8;
00145             ctx->decode_dct_block = dnxhd_decode_dct_block_8;
00146         }
00147     }
00148 
00149     cid = AV_RB32(buf + 0x28);
00150     av_dlog(ctx->avctx, "compression id %d\n", cid);
00151 
00152     if (dnxhd_init_vlc(ctx, cid) < 0)
00153         return -1;
00154 
00155     if (buf_size < ctx->cid_table->coding_unit_size) {
00156         av_log(ctx->avctx, AV_LOG_ERROR, "incorrect frame size\n");
00157         return -1;
00158     }
00159 
00160     ctx->mb_width = ctx->width>>4;
00161     ctx->mb_height = buf[0x16d];
00162 
00163     av_dlog(ctx->avctx, "mb width %d, mb height %d\n", ctx->mb_width, ctx->mb_height);
00164 
00165     if ((ctx->height+15)>>4 == ctx->mb_height && ctx->picture.interlaced_frame)
00166         ctx->height <<= 1;
00167 
00168     if (ctx->mb_height > 68 ||
00169         (ctx->mb_height<<ctx->picture.interlaced_frame) > (ctx->height+15)>>4) {
00170         av_log(ctx->avctx, AV_LOG_ERROR, "mb height too big: %d\n", ctx->mb_height);
00171         return -1;
00172     }
00173 
00174     for (i = 0; i < ctx->mb_height; i++) {
00175         ctx->mb_scan_index[i] = AV_RB32(buf + 0x170 + (i<<2));
00176         av_dlog(ctx->avctx, "mb scan index %d\n", ctx->mb_scan_index[i]);
00177         if (buf_size < ctx->mb_scan_index[i] + 0x280) {
00178             av_log(ctx->avctx, AV_LOG_ERROR, "invalid mb scan index\n");
00179             return -1;
00180         }
00181     }
00182 
00183     return 0;
00184 }
00185 
00186 static av_always_inline void dnxhd_decode_dct_block(DNXHDContext *ctx,
00187                                                     DCTELEM *block, int n,
00188                                                     int qscale,
00189                                                     int index_bits,
00190                                                     int level_bias,
00191                                                     int level_shift)
00192 {
00193     int i, j, index1, index2, len, flags;
00194     int level, component, sign;
00195     const int *scale;
00196     const uint8_t *weight_matrix;
00197     const uint8_t *ac_level = ctx->cid_table->ac_level;
00198     const uint8_t *ac_flags = ctx->cid_table->ac_flags;
00199     const int eob_index     = ctx->cid_table->eob_index;
00200     OPEN_READER(bs, &ctx->gb);
00201 
00202     if (n&2) {
00203         component = 1 + (n&1);
00204         scale = ctx->chroma_scale;
00205         weight_matrix = ctx->cid_table->chroma_weight;
00206     } else {
00207         component = 0;
00208         scale = ctx->luma_scale;
00209         weight_matrix = ctx->cid_table->luma_weight;
00210     }
00211 
00212     UPDATE_CACHE(bs, &ctx->gb);
00213     GET_VLC(len, bs, &ctx->gb, ctx->dc_vlc.table, DNXHD_DC_VLC_BITS, 1);
00214     if (len) {
00215         level = GET_CACHE(bs, &ctx->gb);
00216         LAST_SKIP_BITS(bs, &ctx->gb, len);
00217         sign  = ~level >> 31;
00218         level = (NEG_USR32(sign ^ level, len) ^ sign) - sign;
00219         ctx->last_dc[component] += level;
00220     }
00221     block[0] = ctx->last_dc[component];
00222     //av_log(ctx->avctx, AV_LOG_DEBUG, "dc %d\n", block[0]);
00223 
00224     i = 0;
00225 
00226     UPDATE_CACHE(bs, &ctx->gb);
00227     GET_VLC(index1, bs, &ctx->gb, ctx->ac_vlc.table,
00228             DNXHD_VLC_BITS, 2);
00229 
00230     while (index1 != eob_index) {
00231         level = ac_level[index1];
00232         flags = ac_flags[index1];
00233 
00234         sign = SHOW_SBITS(bs, &ctx->gb, 1);
00235         SKIP_BITS(bs, &ctx->gb, 1);
00236 
00237         if (flags & 1) {
00238             level += SHOW_UBITS(bs, &ctx->gb, index_bits) << 7;
00239             SKIP_BITS(bs, &ctx->gb, index_bits);
00240         }
00241 
00242         if (flags & 2) {
00243             UPDATE_CACHE(bs, &ctx->gb);
00244             GET_VLC(index2, bs, &ctx->gb, ctx->run_vlc.table,
00245                     DNXHD_VLC_BITS, 2);
00246             i += ctx->cid_table->run[index2];
00247         }
00248 
00249         if (++i > 63) {
00250             av_log(ctx->avctx, AV_LOG_ERROR, "ac tex damaged %d, %d\n", n, i);
00251             break;
00252         }
00253 
00254         j = ctx->scantable.permutated[i];
00255         //av_log(ctx->avctx, AV_LOG_DEBUG, "j %d\n", j);
00256         //av_log(ctx->avctx, AV_LOG_DEBUG, "level %d, weight %d\n", level, weight_matrix[i]);
00257         level *= scale[i];
00258         if (level_bias < 32 || weight_matrix[i] != level_bias)
00259             level += level_bias;
00260         level >>= level_shift;
00261 
00262         //av_log(NULL, AV_LOG_DEBUG, "i %d, j %d, end level %d\n", i, j, level);
00263         block[j] = (level^sign) - sign;
00264 
00265         UPDATE_CACHE(bs, &ctx->gb);
00266         GET_VLC(index1, bs, &ctx->gb, ctx->ac_vlc.table,
00267                 DNXHD_VLC_BITS, 2);
00268     }
00269 
00270     CLOSE_READER(bs, &ctx->gb);
00271 }
00272 
00273 static void dnxhd_decode_dct_block_8(DNXHDContext *ctx, DCTELEM *block,
00274                                      int n, int qscale)
00275 {
00276     dnxhd_decode_dct_block(ctx, block, n, qscale, 4, 32, 6);
00277 }
00278 
00279 static void dnxhd_decode_dct_block_10(DNXHDContext *ctx, DCTELEM *block,
00280                                       int n, int qscale)
00281 {
00282     dnxhd_decode_dct_block(ctx, block, n, qscale, 6, 8, 4);
00283 }
00284 
00285 static int dnxhd_decode_macroblock(DNXHDContext *ctx, int x, int y)
00286 {
00287     int shift1 = ctx->bit_depth == 10;
00288     int dct_linesize_luma   = ctx->picture.linesize[0];
00289     int dct_linesize_chroma = ctx->picture.linesize[1];
00290     uint8_t *dest_y, *dest_u, *dest_v;
00291     int dct_y_offset, dct_x_offset;
00292     int qscale, i;
00293 
00294     qscale = get_bits(&ctx->gb, 11);
00295     skip_bits1(&ctx->gb);
00296     //av_log(ctx->avctx, AV_LOG_DEBUG, "qscale %d\n", qscale);
00297 
00298     if (qscale != ctx->last_qscale) {
00299         for (i = 0; i < 64; i++) {
00300             ctx->luma_scale[i]   = qscale * ctx->cid_table->luma_weight[i];
00301             ctx->chroma_scale[i] = qscale * ctx->cid_table->chroma_weight[i];
00302         }
00303         ctx->last_qscale = qscale;
00304     }
00305 
00306     for (i = 0; i < 8; i++) {
00307         ctx->dsp.clear_block(ctx->blocks[i]);
00308         ctx->decode_dct_block(ctx, ctx->blocks[i], i, qscale);
00309     }
00310 
00311     if (ctx->picture.interlaced_frame) {
00312         dct_linesize_luma   <<= 1;
00313         dct_linesize_chroma <<= 1;
00314     }
00315 
00316     dest_y = ctx->picture.data[0] + ((y * dct_linesize_luma)   << 4) + (x << (4 + shift1));
00317     dest_u = ctx->picture.data[1] + ((y * dct_linesize_chroma) << 4) + (x << (3 + shift1));
00318     dest_v = ctx->picture.data[2] + ((y * dct_linesize_chroma) << 4) + (x << (3 + shift1));
00319 
00320     if (ctx->cur_field) {
00321         dest_y += ctx->picture.linesize[0];
00322         dest_u += ctx->picture.linesize[1];
00323         dest_v += ctx->picture.linesize[2];
00324     }
00325 
00326     dct_y_offset = dct_linesize_luma << 3;
00327     dct_x_offset = 8 << shift1;
00328     ctx->dsp.idct_put(dest_y,                               dct_linesize_luma, ctx->blocks[0]);
00329     ctx->dsp.idct_put(dest_y + dct_x_offset,                dct_linesize_luma, ctx->blocks[1]);
00330     ctx->dsp.idct_put(dest_y + dct_y_offset,                dct_linesize_luma, ctx->blocks[4]);
00331     ctx->dsp.idct_put(dest_y + dct_y_offset + dct_x_offset, dct_linesize_luma, ctx->blocks[5]);
00332 
00333     if (!(ctx->avctx->flags & CODEC_FLAG_GRAY)) {
00334         dct_y_offset = dct_linesize_chroma << 3;
00335         ctx->dsp.idct_put(dest_u,                dct_linesize_chroma, ctx->blocks[2]);
00336         ctx->dsp.idct_put(dest_v,                dct_linesize_chroma, ctx->blocks[3]);
00337         ctx->dsp.idct_put(dest_u + dct_y_offset, dct_linesize_chroma, ctx->blocks[6]);
00338         ctx->dsp.idct_put(dest_v + dct_y_offset, dct_linesize_chroma, ctx->blocks[7]);
00339     }
00340 
00341     return 0;
00342 }
00343 
00344 static int dnxhd_decode_macroblocks(DNXHDContext *ctx, const uint8_t *buf, int buf_size)
00345 {
00346     int x, y;
00347     for (y = 0; y < ctx->mb_height; y++) {
00348         ctx->last_dc[0] =
00349         ctx->last_dc[1] =
00350         ctx->last_dc[2] = 1 << (ctx->bit_depth + 2); // for levels +2^(bitdepth-1)
00351         init_get_bits(&ctx->gb, buf + ctx->mb_scan_index[y], (buf_size - ctx->mb_scan_index[y]) << 3);
00352         for (x = 0; x < ctx->mb_width; x++) {
00353             //START_TIMER;
00354             dnxhd_decode_macroblock(ctx, x, y);
00355             //STOP_TIMER("decode macroblock");
00356         }
00357     }
00358     return 0;
00359 }
00360 
00361 static int dnxhd_decode_frame(AVCodecContext *avctx, void *data, int *data_size,
00362                               AVPacket *avpkt)
00363 {
00364     const uint8_t *buf = avpkt->data;
00365     int buf_size = avpkt->size;
00366     DNXHDContext *ctx = avctx->priv_data;
00367     AVFrame *picture = data;
00368     int first_field = 1;
00369     int ret;
00370 
00371     av_dlog(avctx, "frame size %d\n", buf_size);
00372 
00373  decode_coding_unit:
00374     if (dnxhd_decode_header(ctx, buf, buf_size, first_field) < 0)
00375         return -1;
00376 
00377     if ((avctx->width || avctx->height) &&
00378         (ctx->width != avctx->width || ctx->height != avctx->height)) {
00379         av_log(avctx, AV_LOG_WARNING, "frame size changed: %dx%d -> %dx%d\n",
00380                avctx->width, avctx->height, ctx->width, ctx->height);
00381         first_field = 1;
00382     }
00383 
00384     if (av_image_check_size(ctx->width, ctx->height, 0, avctx))
00385         return -1;
00386     avcodec_set_dimensions(avctx, ctx->width, ctx->height);
00387 
00388     if (first_field) {
00389         if (ctx->picture.data[0])
00390             ff_thread_release_buffer(avctx, &ctx->picture);
00391         if ((ret = ff_thread_get_buffer(avctx, &ctx->picture)) < 0) {
00392             av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
00393             return ret;
00394         }
00395     }
00396 
00397     ff_thread_finish_setup(avctx);
00398 
00399     dnxhd_decode_macroblocks(ctx, buf + 0x280, buf_size - 0x280);
00400 
00401     if (first_field && ctx->picture.interlaced_frame) {
00402         buf      += ctx->cid_table->coding_unit_size;
00403         buf_size -= ctx->cid_table->coding_unit_size;
00404         first_field = 0;
00405         goto decode_coding_unit;
00406     }
00407 
00408     *picture = ctx->picture;
00409     *data_size = sizeof(AVPicture);
00410     return buf_size;
00411 }
00412 
00413 static av_cold int dnxhd_decode_close(AVCodecContext *avctx)
00414 {
00415     DNXHDContext *ctx = avctx->priv_data;
00416 
00417     if (ctx->picture.data[0])
00418         ff_thread_release_buffer(avctx, &ctx->picture);
00419     ff_free_vlc(&ctx->ac_vlc);
00420     ff_free_vlc(&ctx->dc_vlc);
00421     ff_free_vlc(&ctx->run_vlc);
00422     return 0;
00423 }
00424 
00425 AVCodec ff_dnxhd_decoder = {
00426     .name           = "dnxhd",
00427     .type           = AVMEDIA_TYPE_VIDEO,
00428     .id             = CODEC_ID_DNXHD,
00429     .priv_data_size = sizeof(DNXHDContext),
00430     .init           = dnxhd_decode_init,
00431     .close          = dnxhd_decode_close,
00432     .decode         = dnxhd_decode_frame,
00433     .capabilities   = CODEC_CAP_DR1 | CODEC_CAP_FRAME_THREADS,
00434     .long_name = NULL_IF_CONFIG_SMALL("VC3/DNxHD"),
00435 };
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