libavcodec/utvideoenc.c

   1 /*
   2  * Ut Video encoder
   3  * Copyright (c) 2012 Jan Ekström
   4  *
   5  * This file is part of Libav.
   6  *
   7  * Libav is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * Libav is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with Libav; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 /**
  23  * @file
  24  * Ut Video encoder
  25  */
  26
  27 #include "libavutil/imgutils.h"
  28 #include "libavutil/intreadwrite.h"
  29 #include "avcodec.h"
  30 #include "internal.h"
  31 #include "bytestream.h"
  32 #include "put_bits.h"
  33 #include "dsputil.h"
  34 #include "mathops.h"
  35 #include "utvideo.h"
  36 #include "huffman.h"
  37
  38 /* Compare huffentry symbols */
  39 static int huff_cmp_sym(const void *a, const void *b)
  40 {
  41     const HuffEntry *aa = a, *bb = b;
  42     return aa->sym - bb->sym;
  43 }
  44
  45 static av_cold int utvideo_encode_close(AVCodecContext *avctx)
  46 {
  47     UtvideoContext *c = avctx->priv_data;
  48     int i;
  49
  50     av_freep(&avctx->coded_frame);
  51     av_freep(&c->slice_bits);
  52     for (i = 0; i < 4; i++)
  53         av_freep(&c->slice_buffer[i]);
  54
  55     return 0;
  56 }
  57
  58 static av_cold int utvideo_encode_init(AVCodecContext *avctx)
  59 {
  60     UtvideoContext *c = avctx->priv_data;
  61     int i;
  62     uint32_t original_format;
  63
  64     c->avctx           = avctx;
  65     c->frame_info_size = 4;
  66     c->slice_stride    = FFALIGN(avctx->width, 32);
  67
  68     switch (avctx->pix_fmt) {
  69     case AV_PIX_FMT_RGB24:
  70         c->planes        = 3;
  71         avctx->codec_tag = MKTAG('U', 'L', 'R', 'G');
  72         original_format  = UTVIDEO_RGB;
  73         break;
  74     case AV_PIX_FMT_RGBA:
  75         c->planes        = 4;
  76         avctx->codec_tag = MKTAG('U', 'L', 'R', 'A');
  77         original_format  = UTVIDEO_RGBA;
  78         break;
  79     case AV_PIX_FMT_YUV420P:
  80         if (avctx->width & 1 || avctx->height & 1) {
  81             av_log(avctx, AV_LOG_ERROR,
  82                    "4:2:0 video requires even width and height.\n");
  83             return AVERROR_INVALIDDATA;
  84         }
  85         c->planes        = 3;
  86         if (avctx->colorspace == AVCOL_SPC_BT709)
  87             avctx->codec_tag = MKTAG('U', 'L', 'H', '0');
  88         else
  89             avctx->codec_tag = MKTAG('U', 'L', 'Y', '0');
  90         original_format  = UTVIDEO_420;
  91         break;
  92     case AV_PIX_FMT_YUV422P:
  93         if (avctx->width & 1) {
  94             av_log(avctx, AV_LOG_ERROR,
  95                    "4:2:2 video requires even width.\n");
  96             return AVERROR_INVALIDDATA;
  97         }
  98         c->planes        = 3;
  99         if (avctx->colorspace == AVCOL_SPC_BT709)
 100             avctx->codec_tag = MKTAG('U', 'L', 'H', '2');
 101         else
 102             avctx->codec_tag = MKTAG('U', 'L', 'Y', '2');
 103         original_format  = UTVIDEO_422;
 104         break;
 105     default:
 106         av_log(avctx, AV_LOG_ERROR, "Unknown pixel format: %d\n",
 107                avctx->pix_fmt);
 108         return AVERROR_INVALIDDATA;
 109     }
 110
 111     ff_dsputil_init(&c->dsp, avctx);
 112
 113     /* Check the prediction method, and error out if unsupported */
 114     if (avctx->prediction_method < 0 || avctx->prediction_method > 4) {
 115         av_log(avctx, AV_LOG_WARNING,
 116                "Prediction method %d is not supported in Ut Video.\n",
 117                avctx->prediction_method);
 118         return AVERROR_OPTION_NOT_FOUND;
 119     }
 120
 121     if (avctx->prediction_method == FF_PRED_PLANE) {
 122         av_log(avctx, AV_LOG_ERROR,
 123                "Plane prediction is not supported in Ut Video.\n");
 124         return AVERROR_OPTION_NOT_FOUND;
 125     }
 126
 127     /* Convert from libavcodec prediction type to Ut Video's */
 128     c->frame_pred = ff_ut_pred_order[avctx->prediction_method];
 129
 130     if (c->frame_pred == PRED_GRADIENT) {
 131         av_log(avctx, AV_LOG_ERROR, "Gradient prediction is not supported.\n");
 132         return AVERROR_OPTION_NOT_FOUND;
 133     }
 134
 135     avctx->coded_frame = av_frame_alloc();
 136
 137     if (!avctx->coded_frame) {
 138         av_log(avctx, AV_LOG_ERROR, "Could not allocate frame.\n");
 139         utvideo_encode_close(avctx);
 140         return AVERROR(ENOMEM);
 141     }
 142
 143     /* extradata size is 4 * 32bit */
 144     avctx->extradata_size = 16;
 145
 146     avctx->extradata = av_mallocz(avctx->extradata_size +
 147                                   FF_INPUT_BUFFER_PADDING_SIZE);
 148
 149     if (!avctx->extradata) {
 150         av_log(avctx, AV_LOG_ERROR, "Could not allocate extradata.\n");
 151         utvideo_encode_close(avctx);
 152         return AVERROR(ENOMEM);
 153     }
 154
 155     for (i = 0; i < c->planes; i++) {
 156         c->slice_buffer[i] = av_malloc(c->slice_stride * (avctx->height + 2) +
 157                                        FF_INPUT_BUFFER_PADDING_SIZE);
 158         if (!c->slice_buffer[i]) {
 159             av_log(avctx, AV_LOG_ERROR, "Cannot allocate temporary buffer 1.\n");
 160             utvideo_encode_close(avctx);
 161             return AVERROR(ENOMEM);
 162         }
 163     }
 164
 165     /*
 166      * Set the version of the encoder.
 167      * Last byte is "implementation ID", which is
 168      * obtained from the creator of the format.
 169      * Libavcodec has been assigned with the ID 0xF0.
 170      */
 171     AV_WB32(avctx->extradata, MKTAG(1, 0, 0, 0xF0));
 172
 173     /*
 174      * Set the "original format"
 175      * Not used for anything during decoding.
 176      */
 177     AV_WL32(avctx->extradata + 4, original_format);
 178
 179     /* Write 4 as the 'frame info size' */
 180     AV_WL32(avctx->extradata + 8, c->frame_info_size);
 181
 182     /*
 183      * Set how many slices are going to be used.
 184      * Set one slice for now.
 185      */
 186     c->slices = 1;
 187
 188     /* Set compression mode */
 189     c->compression = COMP_HUFF;
 190
 191     /*
 192      * Set the encoding flags:
 193      * - Slice count minus 1
 194      * - Interlaced encoding mode flag, set to zero for now.
 195      * - Compression mode (none/huff)
 196      * And write the flags.
 197      */
 198     c->flags  = (c->slices - 1) << 24;
 199     c->flags |= 0 << 11; // bit field to signal interlaced encoding mode
 200     c->flags |= c->compression;
 201
 202     AV_WL32(avctx->extradata + 12, c->flags);
 203
 204     return 0;
 205 }
 206
 207 static void mangle_rgb_planes(uint8_t *dst[4], int dst_stride, uint8_t *src,
 208                               int step, int stride, int width, int height)
 209 {
 210     int i, j;
 211     int k = 2 * dst_stride;
 212     unsigned int g;
 213
 214     for (j = 0; j < height; j++) {
 215         if (step == 3) {
 216             for (i = 0; i < width * step; i += step) {
 217                 g         = src[i + 1];
 218                 dst[0][k] = g;
 219                 g        += 0x80;
 220                 dst[1][k] = src[i + 2] - g;
 221                 dst[2][k] = src[i + 0] - g;
 222                 k++;
 223             }
 224         } else {
 225             for (i = 0; i < width * step; i += step) {
 226                 g         = src[i + 1];
 227                 dst[0][k] = g;
 228                 g        += 0x80;
 229                 dst[1][k] = src[i + 2] - g;
 230                 dst[2][k] = src[i + 0] - g;
 231                 dst[3][k] = src[i + 3];
 232                 k++;
 233             }
 234         }
 235         k += dst_stride - width;
 236         src += stride;
 237     }
 238 }
 239
 240 /* Write data to a plane with left prediction */
 241 static void left_predict(uint8_t *src, uint8_t *dst, int stride,
 242                          int width, int height)
 243 {
 244     int i, j;
 245     uint8_t prev;
 246
 247     prev = 0x80; /* Set the initial value */
 248     for (j = 0; j < height; j++) {
 249         for (i = 0; i < width; i++) {
 250             *dst++ = src[i] - prev;
 251             prev   = src[i];
 252         }
 253         src += stride;
 254     }
 255 }
 256
 257 /* Write data to a plane with median prediction */
 258 static void median_predict(UtvideoContext *c, uint8_t *src, uint8_t *dst, int stride,
 259                            int width, int height)
 260 {
 261     int i, j;
 262     int A, B;
 263     uint8_t prev;
 264
 265     /* First line uses left neighbour prediction */
 266     prev = 0x80; /* Set the initial value */
 267     for (i = 0; i < width; i++) {
 268         *dst++ = src[i] - prev;
 269         prev   = src[i];
 270     }
 271
 272     if (height == 1)
 273         return;
 274
 275     src += stride;
 276
 277     /*
 278      * Second line uses top prediction for the first sample,
 279      * and median for the rest.
 280      */
 281     A = B = 0;
 282
 283     /* Rest of the coded part uses median prediction */
 284     for (j = 1; j < height; j++) {
 285         c->dsp.sub_hfyu_median_prediction(dst, src - stride, src, width, &A, &B);
 286         dst += width;
 287         src += stride;
 288     }
 289 }
 290
 291 /* Count the usage of values in a plane */
 292 static void count_usage(uint8_t *src, int width,
 293                         int height, uint64_t *counts)
 294 {
 295     int i, j;
 296
 297     for (j = 0; j < height; j++) {
 298         for (i = 0; i < width; i++) {
 299             counts[src[i]]++;
 300         }
 301         src += width;
 302     }
 303 }
 304
 305 /* Calculate the actual huffman codes from the code lengths */
 306 static void calculate_codes(HuffEntry *he)
 307 {
 308     int last, i;
 309     uint32_t code;
 310
 311     qsort(he, 256, sizeof(*he), ff_ut_huff_cmp_len);
 312
 313     last = 255;
 314     while (he[last].len == 255 && last)
 315         last--;
 316
 317     code = 1;
 318     for (i = last; i >= 0; i--) {
 319         he[i].code  = code >> (32 - he[i].len);
 320         code       += 0x80000000u >> (he[i].len - 1);
 321     }
 322
 323     qsort(he, 256, sizeof(*he), huff_cmp_sym);
 324 }
 325
 326 /* Write huffman bit codes to a memory block */
 327 static int write_huff_codes(uint8_t *src, uint8_t *dst, int dst_size,
 328                             int width, int height, HuffEntry *he)
 329 {
 330     PutBitContext pb;
 331     int i, j;
 332     int count;
 333
 334     init_put_bits(&pb, dst, dst_size);
 335
 336     /* Write the codes */
 337     for (j = 0; j < height; j++) {
 338         for (i = 0; i < width; i++)
 339             put_bits(&pb, he[src[i]].len, he[src[i]].code);
 340
 341         src += width;
 342     }
 343
 344     /* Pad output to a 32bit boundary */
 345     count = put_bits_count(&pb) & 0x1F;
 346
 347     if (count)
 348         put_bits(&pb, 32 - count, 0);
 349
 350     /* Get the amount of bits written */
 351     count = put_bits_count(&pb);
 352
 353     /* Flush the rest with zeroes */
 354     flush_put_bits(&pb);
 355
 356     return count;
 357 }
 358
 359 static int encode_plane(AVCodecContext *avctx, uint8_t *src,
 360                         uint8_t *dst, int stride,
 361                         int width, int height, PutByteContext *pb)
 362 {
 363     UtvideoContext *c        = avctx->priv_data;
 364     uint8_t  lengths[256];
 365     uint64_t counts[256]     = { 0 };
 366
 367     HuffEntry he[256];
 368
 369     uint32_t offset = 0, slice_len = 0;
 370     int      i, sstart, send = 0;
 371     int      symbol;
 372
 373     /* Do prediction / make planes */
 374     switch (c->frame_pred) {
 375     case PRED_NONE:
 376         for (i = 0; i < c->slices; i++) {
 377             sstart = send;
 378             send   = height * (i + 1) / c->slices;
 379             av_image_copy_plane(dst + sstart * width, width,
 380                                 src + sstart * stride, stride,
 381                                 width, send - sstart);
 382         }
 383         break;
 384     case PRED_LEFT:
 385         for (i = 0; i < c->slices; i++) {
 386             sstart = send;
 387             send   = height * (i + 1) / c->slices;
 388             left_predict(src + sstart * stride, dst + sstart * width,
 389                          stride, width, send - sstart);
 390         }
 391         break;
 392     case PRED_MEDIAN:
 393         for (i = 0; i < c->slices; i++) {
 394             sstart = send;
 395             send   = height * (i + 1) / c->slices;
 396             median_predict(c, src + sstart * stride, dst + sstart * width,
 397                            stride, width, send - sstart);
 398         }
 399         break;
 400     default:
 401         av_log(avctx, AV_LOG_ERROR, "Unknown prediction mode: %d\n",
 402                c->frame_pred);
 403         return AVERROR_OPTION_NOT_FOUND;
 404     }
 405
 406     /* Count the usage of values */
 407     count_usage(dst, width, height, counts);
 408
 409     /* Check for a special case where only one symbol was used */
 410     for (symbol = 0; symbol < 256; symbol++) {
 411         /* If non-zero count is found, see if it matches width * height */
 412         if (counts[symbol]) {
 413             /* Special case if only one symbol was used */
 414             if (counts[symbol] == width * height) {
 415                 /*
 416                  * Write a zero for the single symbol
 417                  * used in the plane, else 0xFF.
 418                  */
 419                 for (i = 0; i < 256; i++) {
 420                     if (i == symbol)
 421                         bytestream2_put_byte(pb, 0);
 422                     else
 423                         bytestream2_put_byte(pb, 0xFF);
 424                 }
 425
 426                 /* Write zeroes for lengths */
 427                 for (i = 0; i < c->slices; i++)
 428                     bytestream2_put_le32(pb, 0);
 429
 430                 /* And that's all for that plane folks */
 431                 return 0;
 432             }
 433             break;
 434         }
 435     }
 436
 437     /* Calculate huffman lengths */
 438     ff_huff_gen_len_table(lengths, counts);
 439
 440     /*
 441      * Write the plane's header into the output packet:
 442      * - huffman code lengths (256 bytes)
 443      * - slice end offsets (gotten from the slice lengths)
 444      */
 445     for (i = 0; i < 256; i++) {
 446         bytestream2_put_byte(pb, lengths[i]);
 447
 448         he[i].len = lengths[i];
 449         he[i].sym = i;
 450     }
 451
 452     /* Calculate the huffman codes themselves */
 453     calculate_codes(he);
 454
 455     send = 0;
 456     for (i = 0; i < c->slices; i++) {
 457         sstart  = send;
 458         send    = height * (i + 1) / c->slices;
 459
 460         /*
 461          * Write the huffman codes to a buffer,
 462          * get the offset in bits and convert to bytes.
 463          */
 464         offset += write_huff_codes(dst + sstart * width, c->slice_bits,
 465                                    width * (send - sstart), width,
 466                                    send - sstart, he) >> 3;
 467
 468         slice_len = offset - slice_len;
 469
 470         /* Byteswap the written huffman codes */
 471         c->dsp.bswap_buf((uint32_t *) c->slice_bits,
 472                          (uint32_t *) c->slice_bits,
 473                          slice_len >> 2);
 474
 475         /* Write the offset to the stream */
 476         bytestream2_put_le32(pb, offset);
 477
 478         /* Seek to the data part of the packet */
 479         bytestream2_seek_p(pb, 4 * (c->slices - i - 1) +
 480                            offset - slice_len, SEEK_CUR);
 481
 482         /* Write the slices' data into the output packet */
 483         bytestream2_put_buffer(pb, c->slice_bits, slice_len);
 484
 485         /* Seek back to the slice offsets */
 486         bytestream2_seek_p(pb, -4 * (c->slices - i - 1) - offset,
 487                            SEEK_CUR);
 488
 489         slice_len = offset;
 490     }
 491
 492     /* And at the end seek to the end of written slice(s) */
 493     bytestream2_seek_p(pb, offset, SEEK_CUR);
 494
 495     return 0;
 496 }
 497
 498 static int utvideo_encode_frame(AVCodecContext *avctx, AVPacket *pkt,
 499                                 const AVFrame *pic, int *got_packet)
 500 {
 501     UtvideoContext *c = avctx->priv_data;
 502     PutByteContext pb;
 503
 504     uint32_t frame_info;
 505
 506     uint8_t *dst;
 507
 508     int width = avctx->width, height = avctx->height;
 509     int i, ret = 0;
 510
 511     /* Allocate a new packet if needed, and set it to the pointer dst */
 512     ret = ff_alloc_packet(pkt, (256 + 4 * c->slices + width * height) *
 513                           c->planes + 4);
 514
 515     if (ret < 0) {
 516         av_log(avctx, AV_LOG_ERROR,
 517                "Error allocating the output packet, or the provided packet "
 518                "was too small.\n");
 519         return ret;
 520     }
 521
 522     dst = pkt->data;
 523
 524     bytestream2_init_writer(&pb, dst, pkt->size);
 525
 526     av_fast_malloc(&c->slice_bits, &c->slice_bits_size,
 527                    width * height + FF_INPUT_BUFFER_PADDING_SIZE);
 528
 529     if (!c->slice_bits) {
 530         av_log(avctx, AV_LOG_ERROR, "Cannot allocate temporary buffer 2.\n");
 531         return AVERROR(ENOMEM);
 532     }
 533
 534     /* In case of RGB, mangle the planes to Ut Video's format */
 535     if (avctx->pix_fmt == AV_PIX_FMT_RGBA || avctx->pix_fmt == AV_PIX_FMT_RGB24)
 536         mangle_rgb_planes(c->slice_buffer, c->slice_stride, pic->data[0],
 537                           c->planes, pic->linesize[0], width, height);
 538
 539     /* Deal with the planes */
 540     switch (avctx->pix_fmt) {
 541     case AV_PIX_FMT_RGB24:
 542     case AV_PIX_FMT_RGBA:
 543         for (i = 0; i < c->planes; i++) {
 544             ret = encode_plane(avctx, c->slice_buffer[i] + 2 * c->slice_stride,
 545                                c->slice_buffer[i], c->slice_stride,
 546                                width, height, &pb);
 547
 548             if (ret) {
 549                 av_log(avctx, AV_LOG_ERROR, "Error encoding plane %d.\n", i);
 550                 return ret;
 551             }
 552         }
 553         break;
 554     case AV_PIX_FMT_YUV422P:
 555         for (i = 0; i < c->planes; i++) {
 556             ret = encode_plane(avctx, pic->data[i], c->slice_buffer[0],
 557                                pic->linesize[i], width >> !!i, height, &pb);
 558
 559             if (ret) {
 560                 av_log(avctx, AV_LOG_ERROR, "Error encoding plane %d.\n", i);
 561                 return ret;
 562             }
 563         }
 564         break;
 565     case AV_PIX_FMT_YUV420P:
 566         for (i = 0; i < c->planes; i++) {
 567             ret = encode_plane(avctx, pic->data[i], c->slice_buffer[0],
 568                                pic->linesize[i], width >> !!i, height >> !!i,
 569                                &pb);
 570
 571             if (ret) {
 572                 av_log(avctx, AV_LOG_ERROR, "Error encoding plane %d.\n", i);
 573                 return ret;
 574             }
 575         }
 576         break;
 577     default:
 578         av_log(avctx, AV_LOG_ERROR, "Unknown pixel format: %d\n",
 579                avctx->pix_fmt);
 580         return AVERROR_INVALIDDATA;
 581     }
 582
 583     /*
 584      * Write frame information (LE 32bit unsigned)
 585      * into the output packet.
 586      * Contains the prediction method.
 587      */
 588     frame_info = c->frame_pred << 8;
 589     bytestream2_put_le32(&pb, frame_info);
 590
 591     /*
 592      * At least currently Ut Video is IDR only.
 593      * Set flags accordingly.
 594      */
 595     avctx->coded_frame->key_frame = 1;
 596     avctx->coded_frame->pict_type = AV_PICTURE_TYPE_I;
 597
 598     pkt->size   = bytestream2_tell_p(&pb);
 599     pkt->flags |= AV_PKT_FLAG_KEY;
 600
 601     /* Packet should be done */
 602     *got_packet = 1;
 603
 604     return 0;
 605 }
 606
 607 AVCodec ff_utvideo_encoder = {
 608     .name           = "utvideo",
 609     .long_name      = NULL_IF_CONFIG_SMALL("Ut Video"),
 610     .type           = AVMEDIA_TYPE_VIDEO,
 611     .id             = AV_CODEC_ID_UTVIDEO,
 612     .priv_data_size = sizeof(UtvideoContext),
 613     .init           = utvideo_encode_init,
 614     .encode2        = utvideo_encode_frame,
 615     .close          = utvideo_encode_close,
 616     .pix_fmts       = (const enum AVPixelFormat[]) {
 617                           AV_PIX_FMT_RGB24, AV_PIX_FMT_RGBA, AV_PIX_FMT_YUV422P,
 618                           AV_PIX_FMT_YUV420P, AV_PIX_FMT_NONE
 619                       },
 620 };