git.sesse.net Git - ffmpeg/blob - libavcodec/videotoolbox.c

   1 /*
   2  * Videotoolbox hardware acceleration
   3  *
   4  * copyright (c) 2012 Sebastien Zwickert
   5  *
   6  * This file is part of FFmpeg.
   7  *
   8  * FFmpeg is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public
  10  * License as published by the Free Software Foundation; either
  11  * version 2.1 of the License, or (at your option) any later version.
  12  *
  13  * FFmpeg is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  16  * Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public
  19  * License along with FFmpeg; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  21  */
  22
  23 #include "config.h"
  24 #include "videotoolbox.h"
  25 #include "libavutil/hwcontext_videotoolbox.h"
  26 #include "vt_internal.h"
  27 #include "libavutil/avutil.h"
  28 #include "libavutil/hwcontext.h"
  29 #include "bytestream.h"
  30 #include "decode.h"
  31 #include "h264dec.h"
  32 #include "hevcdec.h"
  33 #include "mpegvideo.h"
  34 #include <TargetConditionals.h>
  35
  36 #ifndef kVTVideoDecoderSpecification_RequireHardwareAcceleratedVideoDecoder
  37 #  define kVTVideoDecoderSpecification_RequireHardwareAcceleratedVideoDecoder CFSTR("RequireHardwareAcceleratedVideoDecoder")
  38 #endif
  39
  40 #if !HAVE_KCMVIDEOCODECTYPE_HEVC
  41 enum { kCMVideoCodecType_HEVC = 'hvc1' };
  42 #endif
  43
  44 #define VIDEOTOOLBOX_ESDS_EXTRADATA_PADDING  12
  45
  46 static void videotoolbox_buffer_release(void *opaque, uint8_t *data)
  47 {
  48     CVPixelBufferRef cv_buffer = *(CVPixelBufferRef *)data;
  49     CVPixelBufferRelease(cv_buffer);
  50
  51     av_free(data);
  52 }
  53
  54 static int videotoolbox_buffer_copy(VTContext *vtctx,
  55                                     const uint8_t *buffer,
  56                                     uint32_t size)
  57 {
  58     void *tmp;
  59
  60     tmp = av_fast_realloc(vtctx->bitstream,
  61                          &vtctx->allocated_size,
  62                          size);
  63
  64     if (!tmp)
  65         return AVERROR(ENOMEM);
  66
  67     vtctx->bitstream = tmp;
  68     memcpy(vtctx->bitstream, buffer, size);
  69     vtctx->bitstream_size = size;
  70
  71     return 0;
  72 }
  73
  74 static int videotoolbox_postproc_frame(void *avctx, AVFrame *frame)
  75 {
  76     CVPixelBufferRef ref = *(CVPixelBufferRef *)frame->buf[0]->data;
  77
  78     if (!ref) {
  79         av_log(avctx, AV_LOG_ERROR, "No frame decoded?\n");
  80         av_frame_unref(frame);
  81         return AVERROR_EXTERNAL;
  82     }
  83
  84     frame->data[3] = (uint8_t*)ref;
  85
  86     return 0;
  87 }
  88
  89 int ff_videotoolbox_alloc_frame(AVCodecContext *avctx, AVFrame *frame)
  90 {
  91     size_t      size = sizeof(CVPixelBufferRef);
  92     uint8_t    *data = NULL;
  93     AVBufferRef *buf = NULL;
  94     int ret = ff_attach_decode_data(frame);
  95     FrameDecodeData *fdd;
  96     if (ret < 0)
  97         return ret;
  98
  99     data = av_mallocz(size);
 100     if (!data)
 101         return AVERROR(ENOMEM);
 102     buf = av_buffer_create(data, size, videotoolbox_buffer_release, NULL, 0);
 103     if (!buf) {
 104         av_freep(&data);
 105         return AVERROR(ENOMEM);
 106     }
 107     frame->buf[0] = buf;
 108
 109     fdd = (FrameDecodeData*)frame->private_ref->data;
 110     fdd->post_process = videotoolbox_postproc_frame;
 111
 112     frame->width  = avctx->width;
 113     frame->height = avctx->height;
 114     frame->format = avctx->pix_fmt;
 115
 116     return 0;
 117 }
 118
 119 #define AV_W8(p, v) *(p) = (v)
 120
 121 CFDataRef ff_videotoolbox_avcc_extradata_create(AVCodecContext *avctx)
 122 {
 123     VTContext *vtctx = avctx->internal->hwaccel_priv_data;
 124     H264Context *h = avctx->priv_data;
 125     CFDataRef data = NULL;
 126     uint8_t *p;
 127     int vt_extradata_size = 6 + 2 + h->ps.sps->data_size + 3 + h->ps.pps->data_size;
 128     uint8_t *vt_extradata = av_malloc(vt_extradata_size);
 129     if (!vt_extradata)
 130         return NULL;
 131
 132     p = vt_extradata;
 133
 134     AV_W8(p + 0, 1); /* version */
 135     AV_W8(p + 1, h->ps.sps->data[1]); /* profile */
 136     AV_W8(p + 2, h->ps.sps->data[2]); /* profile compat */
 137     AV_W8(p + 3, h->ps.sps->data[3]); /* level */
 138     AV_W8(p + 4, 0xff); /* 6 bits reserved (111111) + 2 bits nal size length - 3 (11) */
 139     AV_W8(p + 5, 0xe1); /* 3 bits reserved (111) + 5 bits number of sps (00001) */
 140     AV_WB16(p + 6, h->ps.sps->data_size);
 141     memcpy(p + 8, h->ps.sps->data, h->ps.sps->data_size);
 142     p += 8 + h->ps.sps->data_size;
 143     AV_W8(p + 0, 1); /* number of pps */
 144     AV_WB16(p + 1, h->ps.pps->data_size);
 145     memcpy(p + 3, h->ps.pps->data, h->ps.pps->data_size);
 146
 147     p += 3 + h->ps.pps->data_size;
 148     av_assert0(p - vt_extradata == vt_extradata_size);
 149
 150     // save sps header (profile/level) used to create decoder session,
 151     // so we can detect changes and recreate it.
 152     if (vtctx)
 153         memcpy(vtctx->sps, h->ps.sps->data + 1, 3);
 154
 155     data = CFDataCreate(kCFAllocatorDefault, vt_extradata, vt_extradata_size);
 156     av_free(vt_extradata);
 157     return data;
 158 }
 159
 160 CFDataRef ff_videotoolbox_hvcc_extradata_create(AVCodecContext *avctx)
 161 {
 162     HEVCContext *h = avctx->priv_data;
 163     const HEVCVPS *vps = (const HEVCVPS *)h->ps.vps_list[0]->data;
 164     const HEVCSPS *sps = (const HEVCSPS *)h->ps.sps_list[0]->data;
 165     int i, num_pps = 0;
 166     const HEVCPPS *pps = h->ps.pps;
 167     PTLCommon ptlc = vps->ptl.general_ptl;
 168     VUI vui = sps->vui;
 169     uint8_t parallelismType;
 170     CFDataRef data = NULL;
 171     uint8_t *p;
 172     int vt_extradata_size = 23 + 5 + vps->data_size + 5 + sps->data_size + 3;
 173     uint8_t *vt_extradata;
 174
 175     for (i = 0; i < HEVC_MAX_PPS_COUNT; i++) {
 176         if (h->ps.pps_list[i]) {
 177             const HEVCPPS *pps = (const HEVCPPS *)h->ps.pps_list[i]->data;
 178             vt_extradata_size += 2 + pps->data_size;
 179             num_pps++;
 180         }
 181     }
 182
 183     vt_extradata = av_malloc(vt_extradata_size);
 184     if (!vt_extradata)
 185         return NULL;
 186     p = vt_extradata;
 187
 188     /* unsigned int(8) configurationVersion = 1; */
 189     AV_W8(p + 0, 1);
 190
 191     /*
 192      * unsigned int(2) general_profile_space;
 193      * unsigned int(1) general_tier_flag;
 194      * unsigned int(5) general_profile_idc;
 195      */
 196     AV_W8(p + 1, ptlc.profile_space << 6 |
 197                  ptlc.tier_flag     << 5 |
 198                  ptlc.profile_idc);
 199
 200     /* unsigned int(32) general_profile_compatibility_flags; */
 201     memcpy(p + 2, ptlc.profile_compatibility_flag, 4);
 202
 203     /* unsigned int(48) general_constraint_indicator_flags; */
 204     AV_W8(p + 6, ptlc.progressive_source_flag    << 7 |
 205                  ptlc.interlaced_source_flag     << 6 |
 206                  ptlc.non_packed_constraint_flag << 5 |
 207                  ptlc.frame_only_constraint_flag << 4);
 208     AV_W8(p + 7, 0);
 209     AV_WN32(p + 8, 0);
 210
 211     /* unsigned int(8) general_level_idc; */
 212     AV_W8(p + 12, ptlc.level_idc);
 213
 214     /*
 215      * bit(4) reserved = ‘1111’b;
 216      * unsigned int(12) min_spatial_segmentation_idc;
 217      */
 218     AV_W8(p + 13, 0xf0 | (vui.min_spatial_segmentation_idc >> 4));
 219     AV_W8(p + 14, vui.min_spatial_segmentation_idc & 0xff);
 220
 221     /*
 222      * bit(6) reserved = ‘111111’b;
 223      * unsigned int(2) parallelismType;
 224      */
 225     if (!vui.min_spatial_segmentation_idc)
 226         parallelismType = 0;
 227     else if (pps->entropy_coding_sync_enabled_flag && pps->tiles_enabled_flag)
 228         parallelismType = 0;
 229     else if (pps->entropy_coding_sync_enabled_flag)
 230         parallelismType = 3;
 231     else if (pps->tiles_enabled_flag)
 232         parallelismType = 2;
 233     else
 234         parallelismType = 1;
 235     AV_W8(p + 15, 0xfc | parallelismType);
 236
 237     /*
 238      * bit(6) reserved = ‘111111’b;
 239      * unsigned int(2) chromaFormat;
 240      */
 241     AV_W8(p + 16, sps->chroma_format_idc | 0xfc);
 242
 243     /*
 244      * bit(5) reserved = ‘11111’b;
 245      * unsigned int(3) bitDepthLumaMinus8;
 246      */
 247     AV_W8(p + 17, (sps->bit_depth - 8) | 0xfc);
 248
 249     /*
 250      * bit(5) reserved = ‘11111’b;
 251      * unsigned int(3) bitDepthChromaMinus8;
 252      */
 253     AV_W8(p + 18, (sps->bit_depth_chroma - 8) | 0xfc);
 254
 255     /* bit(16) avgFrameRate; */
 256     AV_WB16(p + 19, 0);
 257
 258     /*
 259      * bit(2) constantFrameRate;
 260      * bit(3) numTemporalLayers;
 261      * bit(1) temporalIdNested;
 262      * unsigned int(2) lengthSizeMinusOne;
 263      */
 264     AV_W8(p + 21, 0                             << 6 |
 265                   sps->max_sub_layers           << 3 |
 266                   sps->temporal_id_nesting_flag << 2 |
 267                   3);
 268
 269     /* unsigned int(8) numOfArrays; */
 270     AV_W8(p + 22, 3);
 271
 272     p += 23;
 273     /* vps */
 274     /*
 275      * bit(1) array_completeness;
 276      * unsigned int(1) reserved = 0;
 277      * unsigned int(6) NAL_unit_type;
 278      */
 279     AV_W8(p, 1 << 7 |
 280              HEVC_NAL_VPS & 0x3f);
 281     /* unsigned int(16) numNalus; */
 282     AV_WB16(p + 1, 1);
 283     /* unsigned int(16) nalUnitLength; */
 284     AV_WB16(p + 3, vps->data_size);
 285     /* bit(8*nalUnitLength) nalUnit; */
 286     memcpy(p + 5, vps->data, vps->data_size);
 287     p += 5 + vps->data_size;
 288
 289     /* sps */
 290     AV_W8(p, 1 << 7 |
 291              HEVC_NAL_SPS & 0x3f);
 292     AV_WB16(p + 1, 1);
 293     AV_WB16(p + 3, sps->data_size);
 294     memcpy(p + 5, sps->data, sps->data_size);
 295     p += 5 + sps->data_size;
 296
 297     /* pps */
 298     AV_W8(p, 1 << 7 |
 299              HEVC_NAL_PPS & 0x3f);
 300     AV_WB16(p + 1, num_pps);
 301     p += 3;
 302     for (i = 0; i < HEVC_MAX_PPS_COUNT; i++) {
 303         if (h->ps.pps_list[i]) {
 304             const HEVCPPS *pps = (const HEVCPPS *)h->ps.pps_list[i]->data;
 305             AV_WB16(p, pps->data_size);
 306             memcpy(p + 2, pps->data, pps->data_size);
 307             p += 2 + pps->data_size;
 308         }
 309     }
 310
 311     av_assert0(p - vt_extradata == vt_extradata_size);
 312
 313     data = CFDataCreate(kCFAllocatorDefault, vt_extradata, vt_extradata_size);
 314     av_free(vt_extradata);
 315     return data;
 316 }
 317
 318 static int videotoolbox_set_frame(AVCodecContext *avctx, AVFrame *frame)
 319 {
 320     VTContext *vtctx = avctx->internal->hwaccel_priv_data;
 321     if (!frame->buf[0] || frame->data[3]) {
 322         av_log(avctx, AV_LOG_ERROR, "videotoolbox: invalid state\n");
 323         av_frame_unref(frame);
 324         return AVERROR_EXTERNAL;
 325     }
 326
 327     CVPixelBufferRef *ref = (CVPixelBufferRef *)frame->buf[0]->data;
 328
 329     if (*ref)
 330         CVPixelBufferRelease(*ref);
 331
 332     *ref = vtctx->frame;
 333     vtctx->frame = NULL;
 334
 335     return 0;
 336 }
 337
 338 int ff_videotoolbox_h264_start_frame(AVCodecContext *avctx,
 339                                      const uint8_t *buffer,
 340                                      uint32_t size)
 341 {
 342     VTContext *vtctx = avctx->internal->hwaccel_priv_data;
 343     H264Context *h  = avctx->priv_data;
 344
 345     if (h->is_avc == 1) {
 346         return videotoolbox_buffer_copy(vtctx, buffer, size);
 347     }
 348
 349     return 0;
 350 }
 351
 352 static int videotoolbox_h264_decode_params(AVCodecContext *avctx,
 353                                            int type,
 354                                            const uint8_t *buffer,
 355                                            uint32_t size)
 356 {
 357     VTContext *vtctx = avctx->internal->hwaccel_priv_data;
 358     H264Context *h = avctx->priv_data;
 359
 360     // save sps header (profile/level) used to create decoder session
 361     if (!vtctx->sps[0])
 362         memcpy(vtctx->sps, h->ps.sps->data + 1, 3);
 363
 364     if (type == H264_NAL_SPS) {
 365         if (size > 4 && memcmp(vtctx->sps, buffer + 1, 3) != 0) {
 366             vtctx->reconfig_needed = true;
 367             memcpy(vtctx->sps, buffer + 1, 3);
 368         }
 369     }
 370
 371     // pass-through SPS/PPS changes to the decoder
 372     return ff_videotoolbox_h264_decode_slice(avctx, buffer, size);
 373 }
 374
 375 int ff_videotoolbox_h264_decode_slice(AVCodecContext *avctx,
 376                                       const uint8_t *buffer,
 377                                       uint32_t size)
 378 {
 379     VTContext *vtctx = avctx->internal->hwaccel_priv_data;
 380     H264Context *h  = avctx->priv_data;
 381     void *tmp;
 382
 383     if (h->is_avc == 1)
 384         return 0;
 385
 386     tmp = av_fast_realloc(vtctx->bitstream,
 387                           &vtctx->allocated_size,
 388                           vtctx->bitstream_size+size+4);
 389     if (!tmp)
 390         return AVERROR(ENOMEM);
 391
 392     vtctx->bitstream = tmp;
 393
 394     AV_WB32(vtctx->bitstream + vtctx->bitstream_size, size);
 395     memcpy(vtctx->bitstream + vtctx->bitstream_size + 4, buffer, size);
 396
 397     vtctx->bitstream_size += size + 4;
 398
 399     return 0;
 400 }
 401
 402 int ff_videotoolbox_uninit(AVCodecContext *avctx)
 403 {
 404     VTContext *vtctx = avctx->internal->hwaccel_priv_data;
 405     if (vtctx) {
 406         av_freep(&vtctx->bitstream);
 407         if (vtctx->frame)
 408             CVPixelBufferRelease(vtctx->frame);
 409     }
 410
 411     return 0;
 412 }
 413
 414 #if CONFIG_VIDEOTOOLBOX
 415 // Return the AVVideotoolboxContext that matters currently. Where it comes from
 416 // depends on the API used.
 417 static AVVideotoolboxContext *videotoolbox_get_context(AVCodecContext *avctx)
 418 {
 419     // Somewhat tricky because the user can call av_videotoolbox_default_free()
 420     // at any time, even when the codec is closed.
 421     if (avctx->internal && avctx->internal->hwaccel_priv_data) {
 422         VTContext *vtctx = avctx->internal->hwaccel_priv_data;
 423         if (vtctx->vt_ctx)
 424             return vtctx->vt_ctx;
 425     }
 426     return avctx->hwaccel_context;
 427 }
 428
 429 static int videotoolbox_buffer_create(AVCodecContext *avctx, AVFrame *frame)
 430 {
 431     VTContext *vtctx = avctx->internal->hwaccel_priv_data;
 432     CVPixelBufferRef pixbuf = (CVPixelBufferRef)vtctx->frame;
 433     OSType pixel_format = CVPixelBufferGetPixelFormatType(pixbuf);
 434     enum AVPixelFormat sw_format = av_map_videotoolbox_format_to_pixfmt(pixel_format);
 435     int width = CVPixelBufferGetWidth(pixbuf);
 436     int height = CVPixelBufferGetHeight(pixbuf);
 437     AVHWFramesContext *cached_frames;
 438     int ret;
 439
 440     ret = videotoolbox_set_frame(avctx, frame);
 441     if (ret < 0)
 442         return ret;
 443
 444     // Old API code path.
 445     if (!vtctx->cached_hw_frames_ctx)
 446         return 0;
 447
 448     cached_frames = (AVHWFramesContext*)vtctx->cached_hw_frames_ctx->data;
 449
 450     if (cached_frames->sw_format != sw_format ||
 451         cached_frames->width != width ||
 452         cached_frames->height != height) {
 453         AVBufferRef *hw_frames_ctx = av_hwframe_ctx_alloc(cached_frames->device_ref);
 454         AVHWFramesContext *hw_frames;
 455         if (!hw_frames_ctx)
 456             return AVERROR(ENOMEM);
 457
 458         hw_frames = (AVHWFramesContext*)hw_frames_ctx->data;
 459         hw_frames->format = cached_frames->format;
 460         hw_frames->sw_format = sw_format;
 461         hw_frames->width = width;
 462         hw_frames->height = height;
 463
 464         ret = av_hwframe_ctx_init(hw_frames_ctx);
 465         if (ret < 0) {
 466             av_buffer_unref(&hw_frames_ctx);
 467             return ret;
 468         }
 469
 470         av_buffer_unref(&vtctx->cached_hw_frames_ctx);
 471         vtctx->cached_hw_frames_ctx = hw_frames_ctx;
 472     }
 473
 474     av_buffer_unref(&frame->hw_frames_ctx);
 475     frame->hw_frames_ctx = av_buffer_ref(vtctx->cached_hw_frames_ctx);
 476     if (!frame->hw_frames_ctx)
 477         return AVERROR(ENOMEM);
 478
 479     return 0;
 480 }
 481
 482 static void videotoolbox_write_mp4_descr_length(PutByteContext *pb, int length)
 483 {
 484     int i;
 485     uint8_t b;
 486
 487     for (i = 3; i >= 0; i--) {
 488         b = (length >> (i * 7)) & 0x7F;
 489         if (i != 0)
 490             b |= 0x80;
 491
 492         bytestream2_put_byteu(pb, b);
 493     }
 494 }
 495
 496 static CFDataRef videotoolbox_esds_extradata_create(AVCodecContext *avctx)
 497 {
 498     CFDataRef data;
 499     uint8_t *rw_extradata;
 500     PutByteContext pb;
 501     int full_size = 3 + 5 + 13 + 5 + avctx->extradata_size + 3;
 502     // ES_DescrTag data + DecoderConfigDescrTag + data + DecSpecificInfoTag + size + SLConfigDescriptor
 503     int config_size = 13 + 5 + avctx->extradata_size;
 504     int s;
 505
 506     if (!(rw_extradata = av_mallocz(full_size + VIDEOTOOLBOX_ESDS_EXTRADATA_PADDING)))
 507         return NULL;
 508
 509     bytestream2_init_writer(&pb, rw_extradata, full_size + VIDEOTOOLBOX_ESDS_EXTRADATA_PADDING);
 510     bytestream2_put_byteu(&pb, 0);        // version
 511     bytestream2_put_ne24(&pb, 0);         // flags
 512
 513     // elementary stream descriptor
 514     bytestream2_put_byteu(&pb, 0x03);     // ES_DescrTag
 515     videotoolbox_write_mp4_descr_length(&pb, full_size);
 516     bytestream2_put_ne16(&pb, 0);         // esid
 517     bytestream2_put_byteu(&pb, 0);        // stream priority (0-32)
 518
 519     // decoder configuration descriptor
 520     bytestream2_put_byteu(&pb, 0x04);     // DecoderConfigDescrTag
 521     videotoolbox_write_mp4_descr_length(&pb, config_size);
 522     bytestream2_put_byteu(&pb, 32);       // object type indication. 32 = AV_CODEC_ID_MPEG4
 523     bytestream2_put_byteu(&pb, 0x11);     // stream type
 524     bytestream2_put_ne24(&pb, 0);         // buffer size
 525     bytestream2_put_ne32(&pb, 0);         // max bitrate
 526     bytestream2_put_ne32(&pb, 0);         // avg bitrate
 527
 528     // decoder specific descriptor
 529     bytestream2_put_byteu(&pb, 0x05);     ///< DecSpecificInfoTag
 530     videotoolbox_write_mp4_descr_length(&pb, avctx->extradata_size);
 531
 532     bytestream2_put_buffer(&pb, avctx->extradata, avctx->extradata_size);
 533
 534     // SLConfigDescriptor
 535     bytestream2_put_byteu(&pb, 0x06);     // SLConfigDescrTag
 536     bytestream2_put_byteu(&pb, 0x01);     // length
 537     bytestream2_put_byteu(&pb, 0x02);     //
 538
 539     s = bytestream2_size_p(&pb);
 540
 541     data = CFDataCreate(kCFAllocatorDefault, rw_extradata, s);
 542
 543     av_freep(&rw_extradata);
 544     return data;
 545 }
 546
 547 static CMSampleBufferRef videotoolbox_sample_buffer_create(CMFormatDescriptionRef fmt_desc,
 548                                                            void *buffer,
 549                                                            int size)
 550 {
 551     OSStatus status;
 552     CMBlockBufferRef  block_buf;
 553     CMSampleBufferRef sample_buf;
 554
 555     block_buf  = NULL;
 556     sample_buf = NULL;
 557
 558     status = CMBlockBufferCreateWithMemoryBlock(kCFAllocatorDefault,// structureAllocator
 559                                                 buffer,             // memoryBlock
 560                                                 size,               // blockLength
 561                                                 kCFAllocatorNull,   // blockAllocator
 562                                                 NULL,               // customBlockSource
 563                                                 0,                  // offsetToData
 564                                                 size,               // dataLength
 565                                                 0,                  // flags
 566                                                 &block_buf);
 567
 568     if (!status) {
 569         status = CMSampleBufferCreate(kCFAllocatorDefault,  // allocator
 570                                       block_buf,            // dataBuffer
 571                                       TRUE,                 // dataReady
 572                                       0,                    // makeDataReadyCallback
 573                                       0,                    // makeDataReadyRefcon
 574                                       fmt_desc,             // formatDescription
 575                                       1,                    // numSamples
 576                                       0,                    // numSampleTimingEntries
 577                                       NULL,                 // sampleTimingArray
 578                                       0,                    // numSampleSizeEntries
 579                                       NULL,                 // sampleSizeArray
 580                                       &sample_buf);
 581     }
 582
 583     if (block_buf)
 584         CFRelease(block_buf);
 585
 586     return sample_buf;
 587 }
 588
 589 static void videotoolbox_decoder_callback(void *opaque,
 590                                           void *sourceFrameRefCon,
 591                                           OSStatus status,
 592                                           VTDecodeInfoFlags flags,
 593                                           CVImageBufferRef image_buffer,
 594                                           CMTime pts,
 595                                           CMTime duration)
 596 {
 597     AVCodecContext *avctx = opaque;
 598     VTContext *vtctx = avctx->internal->hwaccel_priv_data;
 599
 600     if (vtctx->frame) {
 601         CVPixelBufferRelease(vtctx->frame);
 602         vtctx->frame = NULL;
 603     }
 604
 605     if (!image_buffer) {
 606         av_log(NULL, AV_LOG_DEBUG, "vt decoder cb: output image buffer is null\n");
 607         return;
 608     }
 609
 610     vtctx->frame = CVPixelBufferRetain(image_buffer);
 611 }
 612
 613 static OSStatus videotoolbox_session_decode_frame(AVCodecContext *avctx)
 614 {
 615     OSStatus status;
 616     CMSampleBufferRef sample_buf;
 617     AVVideotoolboxContext *videotoolbox = videotoolbox_get_context(avctx);
 618     VTContext *vtctx = avctx->internal->hwaccel_priv_data;
 619
 620     sample_buf = videotoolbox_sample_buffer_create(videotoolbox->cm_fmt_desc,
 621                                                    vtctx->bitstream,
 622                                                    vtctx->bitstream_size);
 623
 624     if (!sample_buf)
 625         return -1;
 626
 627     status = VTDecompressionSessionDecodeFrame(videotoolbox->session,
 628                                                sample_buf,
 629                                                0,       // decodeFlags
 630                                                NULL,    // sourceFrameRefCon
 631                                                0);      // infoFlagsOut
 632     if (status == noErr)
 633         status = VTDecompressionSessionWaitForAsynchronousFrames(videotoolbox->session);
 634
 635     CFRelease(sample_buf);
 636
 637     return status;
 638 }
 639
 640 static CMVideoFormatDescriptionRef videotoolbox_format_desc_create(CMVideoCodecType codec_type,
 641                                                                    CFDictionaryRef decoder_spec,
 642                                                                    int width,
 643                                                                    int height)
 644 {
 645     CMFormatDescriptionRef cm_fmt_desc;
 646     OSStatus status;
 647
 648     status = CMVideoFormatDescriptionCreate(kCFAllocatorDefault,
 649                                             codec_type,
 650                                             width,
 651                                             height,
 652                                             decoder_spec, // Dictionary of extension
 653                                             &cm_fmt_desc);
 654
 655     if (status)
 656         return NULL;
 657
 658     return cm_fmt_desc;
 659 }
 660
 661 static CFDictionaryRef videotoolbox_buffer_attributes_create(int width,
 662                                                              int height,
 663                                                              OSType pix_fmt)
 664 {
 665     CFMutableDictionaryRef buffer_attributes;
 666     CFMutableDictionaryRef io_surface_properties;
 667     CFNumberRef cv_pix_fmt;
 668     CFNumberRef w;
 669     CFNumberRef h;
 670
 671     w = CFNumberCreate(kCFAllocatorDefault, kCFNumberSInt32Type, &width);
 672     h = CFNumberCreate(kCFAllocatorDefault, kCFNumberSInt32Type, &height);
 673     cv_pix_fmt = CFNumberCreate(kCFAllocatorDefault, kCFNumberSInt32Type, &pix_fmt);
 674
 675     buffer_attributes = CFDictionaryCreateMutable(kCFAllocatorDefault,
 676                                                   4,
 677                                                   &kCFTypeDictionaryKeyCallBacks,
 678                                                   &kCFTypeDictionaryValueCallBacks);
 679     io_surface_properties = CFDictionaryCreateMutable(kCFAllocatorDefault,
 680                                                       0,
 681                                                       &kCFTypeDictionaryKeyCallBacks,
 682                                                       &kCFTypeDictionaryValueCallBacks);
 683
 684     if (pix_fmt)
 685         CFDictionarySetValue(buffer_attributes, kCVPixelBufferPixelFormatTypeKey, cv_pix_fmt);
 686     CFDictionarySetValue(buffer_attributes, kCVPixelBufferIOSurfacePropertiesKey, io_surface_properties);
 687     CFDictionarySetValue(buffer_attributes, kCVPixelBufferWidthKey, w);
 688     CFDictionarySetValue(buffer_attributes, kCVPixelBufferHeightKey, h);
 689 #if TARGET_OS_IPHONE
 690     CFDictionarySetValue(buffer_attributes, kCVPixelBufferOpenGLESCompatibilityKey, kCFBooleanTrue);
 691 #else
 692     CFDictionarySetValue(buffer_attributes, kCVPixelBufferIOSurfaceOpenGLTextureCompatibilityKey, kCFBooleanTrue);
 693 #endif
 694
 695     CFRelease(io_surface_properties);
 696     CFRelease(cv_pix_fmt);
 697     CFRelease(w);
 698     CFRelease(h);
 699
 700     return buffer_attributes;
 701 }
 702
 703 static CFDictionaryRef videotoolbox_decoder_config_create(CMVideoCodecType codec_type,
 704                                                           AVCodecContext *avctx)
 705 {
 706     CFMutableDictionaryRef config_info = CFDictionaryCreateMutable(kCFAllocatorDefault,
 707                                                                    0,
 708                                                                    &kCFTypeDictionaryKeyCallBacks,
 709                                                                    &kCFTypeDictionaryValueCallBacks);
 710
 711     CFDictionarySetValue(config_info,
 712                          kVTVideoDecoderSpecification_RequireHardwareAcceleratedVideoDecoder,
 713                          kCFBooleanTrue);
 714
 715     CFMutableDictionaryRef avc_info;
 716     CFDataRef data = NULL;
 717
 718     avc_info = CFDictionaryCreateMutable(kCFAllocatorDefault,
 719                                          1,
 720                                          &kCFTypeDictionaryKeyCallBacks,
 721                                          &kCFTypeDictionaryValueCallBacks);
 722
 723     switch (codec_type) {
 724     case kCMVideoCodecType_MPEG4Video :
 725         if (avctx->extradata_size)
 726             data = videotoolbox_esds_extradata_create(avctx);
 727         if (data)
 728             CFDictionarySetValue(avc_info, CFSTR("esds"), data);
 729         break;
 730     case kCMVideoCodecType_H264 :
 731         data = ff_videotoolbox_avcc_extradata_create(avctx);
 732         if (data)
 733             CFDictionarySetValue(avc_info, CFSTR("avcC"), data);
 734         break;
 735     case kCMVideoCodecType_HEVC :
 736         data = ff_videotoolbox_hvcc_extradata_create(avctx);
 737         if (data)
 738             CFDictionarySetValue(avc_info, CFSTR("hvcC"), data);
 739         break;
 740     default:
 741         break;
 742     }
 743
 744     CFDictionarySetValue(config_info,
 745             kCMFormatDescriptionExtension_SampleDescriptionExtensionAtoms,
 746             avc_info);
 747
 748     if (data)
 749         CFRelease(data);
 750
 751     CFRelease(avc_info);
 752     return config_info;
 753 }
 754
 755 static int videotoolbox_start(AVCodecContext *avctx)
 756 {
 757     AVVideotoolboxContext *videotoolbox = videotoolbox_get_context(avctx);
 758     OSStatus status;
 759     VTDecompressionOutputCallbackRecord decoder_cb;
 760     CFDictionaryRef decoder_spec;
 761     CFDictionaryRef buf_attr;
 762
 763     if (!videotoolbox) {
 764         av_log(avctx, AV_LOG_ERROR, "hwaccel context is not set\n");
 765         return -1;
 766     }
 767
 768     switch( avctx->codec_id ) {
 769     case AV_CODEC_ID_H263 :
 770         videotoolbox->cm_codec_type = kCMVideoCodecType_H263;
 771         break;
 772     case AV_CODEC_ID_H264 :
 773         videotoolbox->cm_codec_type = kCMVideoCodecType_H264;
 774         break;
 775     case AV_CODEC_ID_HEVC :
 776         videotoolbox->cm_codec_type = kCMVideoCodecType_HEVC;
 777         break;
 778     case AV_CODEC_ID_MPEG1VIDEO :
 779         videotoolbox->cm_codec_type = kCMVideoCodecType_MPEG1Video;
 780         break;
 781     case AV_CODEC_ID_MPEG2VIDEO :
 782         videotoolbox->cm_codec_type = kCMVideoCodecType_MPEG2Video;
 783         break;
 784     case AV_CODEC_ID_MPEG4 :
 785         videotoolbox->cm_codec_type = kCMVideoCodecType_MPEG4Video;
 786         break;
 787     default :
 788         break;
 789     }
 790
 791     decoder_spec = videotoolbox_decoder_config_create(videotoolbox->cm_codec_type, avctx);
 792
 793     if (!decoder_spec) {
 794         av_log(avctx, AV_LOG_ERROR, "decoder specification creation failed\n");
 795         return -1;
 796     }
 797
 798     videotoolbox->cm_fmt_desc = videotoolbox_format_desc_create(videotoolbox->cm_codec_type,
 799                                                                 decoder_spec,
 800                                                                 avctx->width,
 801                                                                 avctx->height);
 802     if (!videotoolbox->cm_fmt_desc) {
 803         if (decoder_spec)
 804             CFRelease(decoder_spec);
 805
 806         av_log(avctx, AV_LOG_ERROR, "format description creation failed\n");
 807         return -1;
 808     }
 809
 810     buf_attr = videotoolbox_buffer_attributes_create(avctx->width,
 811                                                      avctx->height,
 812                                                      videotoolbox->cv_pix_fmt_type);
 813
 814     decoder_cb.decompressionOutputCallback = videotoolbox_decoder_callback;
 815     decoder_cb.decompressionOutputRefCon   = avctx;
 816
 817     status = VTDecompressionSessionCreate(NULL,                      // allocator
 818                                           videotoolbox->cm_fmt_desc, // videoFormatDescription
 819                                           decoder_spec,              // videoDecoderSpecification
 820                                           buf_attr,                  // destinationImageBufferAttributes
 821                                           &decoder_cb,               // outputCallback
 822                                           &videotoolbox->session);   // decompressionSessionOut
 823
 824     if (decoder_spec)
 825         CFRelease(decoder_spec);
 826     if (buf_attr)
 827         CFRelease(buf_attr);
 828
 829     switch (status) {
 830     case kVTVideoDecoderNotAvailableNowErr:
 831         av_log(avctx, AV_LOG_VERBOSE, "VideoToolbox session not available.\n");
 832         return AVERROR(ENOSYS);
 833     case kVTVideoDecoderUnsupportedDataFormatErr:
 834         av_log(avctx, AV_LOG_VERBOSE, "VideoToolbox does not support this format.\n");
 835         return AVERROR(ENOSYS);
 836     case kVTVideoDecoderMalfunctionErr:
 837         av_log(avctx, AV_LOG_VERBOSE, "VideoToolbox malfunction.\n");
 838         return AVERROR(EINVAL);
 839     case kVTVideoDecoderBadDataErr:
 840         av_log(avctx, AV_LOG_VERBOSE, "VideoToolbox reported invalid data.\n");
 841         return AVERROR_INVALIDDATA;
 842     case 0:
 843         return 0;
 844     default:
 845         av_log(avctx, AV_LOG_VERBOSE, "Unknown VideoToolbox session creation error %u\n", (unsigned)status);
 846         return AVERROR_UNKNOWN;
 847     }
 848 }
 849
 850 static void videotoolbox_stop(AVCodecContext *avctx)
 851 {
 852     AVVideotoolboxContext *videotoolbox = videotoolbox_get_context(avctx);
 853     if (!videotoolbox)
 854         return;
 855
 856     if (videotoolbox->cm_fmt_desc) {
 857         CFRelease(videotoolbox->cm_fmt_desc);
 858         videotoolbox->cm_fmt_desc = NULL;
 859     }
 860
 861     if (videotoolbox->session) {
 862         VTDecompressionSessionInvalidate(videotoolbox->session);
 863         CFRelease(videotoolbox->session);
 864         videotoolbox->session = NULL;
 865     }
 866 }
 867
 868 static const char *videotoolbox_error_string(OSStatus status)
 869 {
 870     switch (status) {
 871         case kVTVideoDecoderBadDataErr:
 872             return "bad data";
 873         case kVTVideoDecoderMalfunctionErr:
 874             return "decoder malfunction";
 875         case kVTInvalidSessionErr:
 876             return "invalid session";
 877     }
 878     return "unknown";
 879 }
 880
 881 static int videotoolbox_common_end_frame(AVCodecContext *avctx, AVFrame *frame)
 882 {
 883     OSStatus status;
 884     AVVideotoolboxContext *videotoolbox = videotoolbox_get_context(avctx);
 885     VTContext *vtctx = avctx->internal->hwaccel_priv_data;
 886
 887     if (vtctx->reconfig_needed == true) {
 888         vtctx->reconfig_needed = false;
 889         av_log(avctx, AV_LOG_VERBOSE, "VideoToolbox decoder needs reconfig, restarting..\n");
 890         videotoolbox_stop(avctx);
 891         if (videotoolbox_start(avctx) != 0) {
 892             return AVERROR_EXTERNAL;
 893         }
 894     }
 895
 896     if (!videotoolbox->session || !vtctx->bitstream || !vtctx->bitstream_size)
 897         return AVERROR_INVALIDDATA;
 898
 899     status = videotoolbox_session_decode_frame(avctx);
 900     if (status != noErr) {
 901         if (status == kVTVideoDecoderMalfunctionErr || status == kVTInvalidSessionErr)
 902             vtctx->reconfig_needed = true;
 903         av_log(avctx, AV_LOG_ERROR, "Failed to decode frame (%s, %d)\n", videotoolbox_error_string(status), (int)status);
 904         return AVERROR_UNKNOWN;
 905     }
 906
 907     if (!vtctx->frame) {
 908         vtctx->reconfig_needed = true;
 909         return AVERROR_UNKNOWN;
 910     }
 911
 912     return videotoolbox_buffer_create(avctx, frame);
 913 }
 914
 915 static int videotoolbox_h264_end_frame(AVCodecContext *avctx)
 916 {
 917     H264Context *h = avctx->priv_data;
 918     AVFrame *frame = h->cur_pic_ptr->f;
 919     VTContext *vtctx = avctx->internal->hwaccel_priv_data;
 920     int ret = videotoolbox_common_end_frame(avctx, frame);
 921     vtctx->bitstream_size = 0;
 922     return ret;
 923 }
 924
 925 static int videotoolbox_hevc_decode_params(AVCodecContext *avctx,
 926                                            int type,
 927                                            const uint8_t *buffer,
 928                                            uint32_t size)
 929 {
 930     return ff_videotoolbox_h264_decode_slice(avctx, buffer, size);
 931 }
 932
 933 static int videotoolbox_hevc_end_frame(AVCodecContext *avctx)
 934 {
 935     HEVCContext *h = avctx->priv_data;
 936     AVFrame *frame = h->ref->frame;
 937     VTContext *vtctx = avctx->internal->hwaccel_priv_data;
 938     int ret;
 939
 940     ret = videotoolbox_common_end_frame(avctx, frame);
 941     vtctx->bitstream_size = 0;
 942     return ret;
 943 }
 944
 945 static int videotoolbox_mpeg_start_frame(AVCodecContext *avctx,
 946                                          const uint8_t *buffer,
 947                                          uint32_t size)
 948 {
 949     VTContext *vtctx = avctx->internal->hwaccel_priv_data;
 950
 951     return videotoolbox_buffer_copy(vtctx, buffer, size);
 952 }
 953
 954 static int videotoolbox_mpeg_decode_slice(AVCodecContext *avctx,
 955                                           const uint8_t *buffer,
 956                                           uint32_t size)
 957 {
 958     return 0;
 959 }
 960
 961 static int videotoolbox_mpeg_end_frame(AVCodecContext *avctx)
 962 {
 963     MpegEncContext *s = avctx->priv_data;
 964     AVFrame *frame = s->current_picture_ptr->f;
 965
 966     return videotoolbox_common_end_frame(avctx, frame);
 967 }
 968
 969 static int videotoolbox_uninit(AVCodecContext *avctx)
 970 {
 971     VTContext *vtctx = avctx->internal->hwaccel_priv_data;
 972     if (!vtctx)
 973         return 0;
 974
 975     ff_videotoolbox_uninit(avctx);
 976
 977     if (vtctx->vt_ctx)
 978         videotoolbox_stop(avctx);
 979
 980     av_buffer_unref(&vtctx->cached_hw_frames_ctx);
 981     av_freep(&vtctx->vt_ctx);
 982
 983     return 0;
 984 }
 985
 986 static int videotoolbox_common_init(AVCodecContext *avctx)
 987 {
 988     VTContext *vtctx = avctx->internal->hwaccel_priv_data;
 989     AVHWFramesContext *hw_frames;
 990     int err;
 991
 992     // Old API - do nothing.
 993     if (avctx->hwaccel_context)
 994         return 0;
 995
 996     if (!avctx->hw_frames_ctx && !avctx->hw_device_ctx) {
 997         av_log(avctx, AV_LOG_ERROR,
 998                "Either hw_frames_ctx or hw_device_ctx must be set.\n");
 999         return AVERROR(EINVAL);
1000     }
1001
1002     vtctx->vt_ctx = av_videotoolbox_alloc_context();
1003     if (!vtctx->vt_ctx) {
1004         err = AVERROR(ENOMEM);
1005         goto fail;
1006     }
1007
1008     if (avctx->hw_frames_ctx) {
1009         hw_frames = (AVHWFramesContext*)avctx->hw_frames_ctx->data;
1010     } else {
1011         avctx->hw_frames_ctx = av_hwframe_ctx_alloc(avctx->hw_device_ctx);
1012         if (!avctx->hw_frames_ctx) {
1013             err = AVERROR(ENOMEM);
1014             goto fail;
1015         }
1016
1017         hw_frames = (AVHWFramesContext*)avctx->hw_frames_ctx->data;
1018         hw_frames->format = AV_PIX_FMT_VIDEOTOOLBOX;
1019         hw_frames->sw_format = AV_PIX_FMT_NV12; // same as av_videotoolbox_alloc_context()
1020         hw_frames->width = avctx->width;
1021         hw_frames->height = avctx->height;
1022
1023         err = av_hwframe_ctx_init(avctx->hw_frames_ctx);
1024         if (err < 0) {
1025             av_buffer_unref(&avctx->hw_frames_ctx);
1026             goto fail;
1027         }
1028     }
1029
1030     vtctx->cached_hw_frames_ctx = av_buffer_ref(avctx->hw_frames_ctx);
1031     if (!vtctx->cached_hw_frames_ctx) {
1032         err = AVERROR(ENOMEM);
1033         goto fail;
1034     }
1035
1036     vtctx->vt_ctx->cv_pix_fmt_type =
1037         av_map_videotoolbox_format_from_pixfmt(hw_frames->sw_format);
1038     if (!vtctx->vt_ctx->cv_pix_fmt_type) {
1039         av_log(avctx, AV_LOG_ERROR, "Unknown sw_format.\n");
1040         err = AVERROR(EINVAL);
1041         goto fail;
1042     }
1043
1044     err = videotoolbox_start(avctx);
1045     if (err < 0)
1046         goto fail;
1047
1048     return 0;
1049
1050 fail:
1051     videotoolbox_uninit(avctx);
1052     return err;
1053 }
1054
1055 static int videotoolbox_frame_params(AVCodecContext *avctx,
1056                                      AVBufferRef *hw_frames_ctx)
1057 {
1058     AVHWFramesContext *frames_ctx = (AVHWFramesContext*)hw_frames_ctx->data;
1059
1060     frames_ctx->format            = AV_PIX_FMT_VIDEOTOOLBOX;
1061     frames_ctx->width             = avctx->coded_width;
1062     frames_ctx->height            = avctx->coded_height;
1063     frames_ctx->sw_format         = AV_PIX_FMT_NV12;
1064
1065     return 0;
1066 }
1067
1068 const AVHWAccel ff_h263_videotoolbox_hwaccel = {
1069     .name           = "h263_videotoolbox",
1070     .type           = AVMEDIA_TYPE_VIDEO,
1071     .id             = AV_CODEC_ID_H263,
1072     .pix_fmt        = AV_PIX_FMT_VIDEOTOOLBOX,
1073     .alloc_frame    = ff_videotoolbox_alloc_frame,
1074     .start_frame    = videotoolbox_mpeg_start_frame,
1075     .decode_slice   = videotoolbox_mpeg_decode_slice,
1076     .end_frame      = videotoolbox_mpeg_end_frame,
1077     .frame_params   = videotoolbox_frame_params,
1078     .init           = videotoolbox_common_init,
1079     .uninit         = videotoolbox_uninit,
1080     .priv_data_size = sizeof(VTContext),
1081 };
1082
1083 const AVHWAccel ff_hevc_videotoolbox_hwaccel = {
1084     .name           = "hevc_videotoolbox",
1085     .type           = AVMEDIA_TYPE_VIDEO,
1086     .id             = AV_CODEC_ID_HEVC,
1087     .pix_fmt        = AV_PIX_FMT_VIDEOTOOLBOX,
1088     .alloc_frame    = ff_videotoolbox_alloc_frame,
1089     .start_frame    = ff_videotoolbox_h264_start_frame,
1090     .decode_slice   = ff_videotoolbox_h264_decode_slice,
1091     .decode_params  = videotoolbox_hevc_decode_params,
1092     .end_frame      = videotoolbox_hevc_end_frame,
1093     .frame_params   = videotoolbox_frame_params,
1094     .init           = videotoolbox_common_init,
1095     .uninit         = ff_videotoolbox_uninit,
1096     .priv_data_size = sizeof(VTContext),
1097 };
1098
1099 const AVHWAccel ff_h264_videotoolbox_hwaccel = {
1100     .name           = "h264_videotoolbox",
1101     .type           = AVMEDIA_TYPE_VIDEO,
1102     .id             = AV_CODEC_ID_H264,
1103     .pix_fmt        = AV_PIX_FMT_VIDEOTOOLBOX,
1104     .alloc_frame    = ff_videotoolbox_alloc_frame,
1105     .start_frame    = ff_videotoolbox_h264_start_frame,
1106     .decode_slice   = ff_videotoolbox_h264_decode_slice,
1107     .decode_params  = videotoolbox_h264_decode_params,
1108     .end_frame      = videotoolbox_h264_end_frame,
1109     .frame_params   = videotoolbox_frame_params,
1110     .init           = videotoolbox_common_init,
1111     .uninit         = videotoolbox_uninit,
1112     .priv_data_size = sizeof(VTContext),
1113 };
1114
1115 const AVHWAccel ff_mpeg1_videotoolbox_hwaccel = {
1116     .name           = "mpeg1_videotoolbox",
1117     .type           = AVMEDIA_TYPE_VIDEO,
1118     .id             = AV_CODEC_ID_MPEG1VIDEO,
1119     .pix_fmt        = AV_PIX_FMT_VIDEOTOOLBOX,
1120     .alloc_frame    = ff_videotoolbox_alloc_frame,
1121     .start_frame    = videotoolbox_mpeg_start_frame,
1122     .decode_slice   = videotoolbox_mpeg_decode_slice,
1123     .end_frame      = videotoolbox_mpeg_end_frame,
1124     .frame_params   = videotoolbox_frame_params,
1125     .init           = videotoolbox_common_init,
1126     .uninit         = videotoolbox_uninit,
1127     .priv_data_size = sizeof(VTContext),
1128 };
1129
1130 const AVHWAccel ff_mpeg2_videotoolbox_hwaccel = {
1131     .name           = "mpeg2_videotoolbox",
1132     .type           = AVMEDIA_TYPE_VIDEO,
1133     .id             = AV_CODEC_ID_MPEG2VIDEO,
1134     .pix_fmt        = AV_PIX_FMT_VIDEOTOOLBOX,
1135     .alloc_frame    = ff_videotoolbox_alloc_frame,
1136     .start_frame    = videotoolbox_mpeg_start_frame,
1137     .decode_slice   = videotoolbox_mpeg_decode_slice,
1138     .end_frame      = videotoolbox_mpeg_end_frame,
1139     .frame_params   = videotoolbox_frame_params,
1140     .init           = videotoolbox_common_init,
1141     .uninit         = videotoolbox_uninit,
1142     .priv_data_size = sizeof(VTContext),
1143 };
1144
1145 const AVHWAccel ff_mpeg4_videotoolbox_hwaccel = {
1146     .name           = "mpeg4_videotoolbox",
1147     .type           = AVMEDIA_TYPE_VIDEO,
1148     .id             = AV_CODEC_ID_MPEG4,
1149     .pix_fmt        = AV_PIX_FMT_VIDEOTOOLBOX,
1150     .alloc_frame    = ff_videotoolbox_alloc_frame,
1151     .start_frame    = videotoolbox_mpeg_start_frame,
1152     .decode_slice   = videotoolbox_mpeg_decode_slice,
1153     .end_frame      = videotoolbox_mpeg_end_frame,
1154     .frame_params   = videotoolbox_frame_params,
1155     .init           = videotoolbox_common_init,
1156     .uninit         = videotoolbox_uninit,
1157     .priv_data_size = sizeof(VTContext),
1158 };
1159
1160 AVVideotoolboxContext *av_videotoolbox_alloc_context(void)
1161 {
1162     AVVideotoolboxContext *ret = av_mallocz(sizeof(*ret));
1163
1164     if (ret) {
1165         ret->output_callback = videotoolbox_decoder_callback;
1166         ret->cv_pix_fmt_type = kCVPixelFormatType_420YpCbCr8BiPlanarVideoRange;
1167     }
1168
1169     return ret;
1170 }
1171
1172 int av_videotoolbox_default_init(AVCodecContext *avctx)
1173 {
1174     return av_videotoolbox_default_init2(avctx, NULL);
1175 }
1176
1177 int av_videotoolbox_default_init2(AVCodecContext *avctx, AVVideotoolboxContext *vtctx)
1178 {
1179     avctx->hwaccel_context = vtctx ?: av_videotoolbox_alloc_context();
1180     if (!avctx->hwaccel_context)
1181         return AVERROR(ENOMEM);
1182     return videotoolbox_start(avctx);
1183 }
1184
1185 void av_videotoolbox_default_free(AVCodecContext *avctx)
1186 {
1187
1188     videotoolbox_stop(avctx);
1189     av_freep(&avctx->hwaccel_context);
1190 }
1191 #endif /* CONFIG_VIDEOTOOLBOX */