avcodec: add new Videotoolbox hwaccel.

1 files changed, 690 insertions, 0 deletions

diff --git a/libavcodec/videotoolbox.c b/libavcodec/videotoolbox.c
new file mode 100644
index 0000000000..cdb314b29b
--- /dev/null
+++ b/libavcodec/videotoolbox.c
@@ -0,0 +1,690 @@
+/*
+ * Videotoolbox hardware acceleration
+ *
+ * copyright (c) 2012 Sebastien Zwickert
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "config.h"
+#if CONFIG_VIDEOTOOLBOX
+#  include "videotoolbox.h"
+#else
+#  include "vda.h"
+#endif
+#include "vda_vt_internal.h"
+#include "libavutil/avutil.h"
+#include "bytestream.h"
+#include "h264.h"
+#include "mpegvideo.h"
+
+#ifndef kVTVideoDecoderSpecification_EnableHardwareAcceleratedVideoDecoder
+#  define kVTVideoDecoderSpecification_EnableHardwareAcceleratedVideoDecoder CFSTR("EnableHardwareAcceleratedVideoDecoder")
+#endif
+
+#define VIDEOTOOLBOX_ESDS_EXTRADATA_PADDING  12
+
+static void videotoolbox_buffer_release(void *opaque, uint8_t *data)
+{
+    CVPixelBufferRef cv_buffer = (CVImageBufferRef)data;
+    CVPixelBufferRelease(cv_buffer);
+}
+
+static int videotoolbox_buffer_copy(VTContext *vtctx,
+                                    const uint8_t *buffer,
+                                    uint32_t size)
+{
+    void *tmp;
+
+    tmp = av_fast_realloc(vtctx->bitstream,
+                         &vtctx->allocated_size,
+                         size);
+
+    if (!tmp)
+        return AVERROR(ENOMEM);
+
+    vtctx->bitstream = tmp;
+    memcpy(vtctx->bitstream, buffer, size);
+    vtctx->bitstream_size = size;
+
+    return 0;
+}
+
+int ff_videotoolbox_alloc_frame(AVCodecContext *avctx, AVFrame *frame)
+{
+    frame->width  = avctx->width;
+    frame->height = avctx->height;
+    frame->format = avctx->pix_fmt;
+    frame->buf[0] = av_buffer_alloc(1);
+
+    if (!frame->buf[0])
+        return AVERROR(ENOMEM);
+
+    return 0;
+}
+
+CFDataRef ff_videotoolbox_avcc_extradata_create(AVCodecContext *avctx)
+{
+    CFDataRef data = NULL;
+
+    /* Each VCL NAL in the bistream sent to the decoder
+     * is preceded by a 4 bytes length header.
+     * Change the avcC atom header if needed, to signal headers of 4 bytes. */
+    if (avctx->extradata_size >= 4 && (avctx->extradata[4] & 0x03) != 0x03) {
+        uint8_t *rw_extradata = av_memdup(avctx->extradata, avctx->extradata_size);
+
+        if (!rw_extradata)
+            return NULL;
+
+        rw_extradata[4] |= 0x03;
+
+        data = CFDataCreate(kCFAllocatorDefault, rw_extradata, avctx->extradata_size);
+
+        av_freep(&rw_extradata);
+    } else {
+        data = CFDataCreate(kCFAllocatorDefault, avctx->extradata, avctx->extradata_size);
+    }
+
+    return data;
+}
+
+int ff_videotoolbox_buffer_create(VTContext *vtctx, AVFrame *frame)
+{
+    av_buffer_unref(&frame->buf[0]);
+
+    frame->buf[0] = av_buffer_create((uint8_t*)vtctx->frame,
+                                     sizeof(vtctx->frame),
+                                     videotoolbox_buffer_release,
+                                     NULL,
+                                     AV_BUFFER_FLAG_READONLY);
+    if (!frame->buf[0]) {
+        return AVERROR(ENOMEM);
+    }
+
+    frame->data[3] = (uint8_t*)vtctx->frame;
+    vtctx->frame = NULL;
+
+    return 0;
+}
+
+int ff_videotoolbox_h264_start_frame(AVCodecContext *avctx,
+                                     const uint8_t *buffer,
+                                     uint32_t size)
+{
+    VTContext *vtctx = avctx->internal->hwaccel_priv_data;
+    H264Context *h  = avctx->priv_data;
+
+    vtctx->bitstream_size = 0;
+
+    if (h->is_avc == 1) {
+        return videotoolbox_buffer_copy(vtctx, buffer, size);
+    }
+
+    return 0;
+}
+
+int ff_videotoolbox_h264_decode_slice(AVCodecContext *avctx,
+                                      const uint8_t *buffer,
+                                      uint32_t size)
+{
+    VTContext *vtctx = avctx->internal->hwaccel_priv_data;
+    H264Context *h  = avctx->priv_data;
+    void *tmp;
+
+    if (h->is_avc == 1)
+        return 0;
+
+    tmp = av_fast_realloc(vtctx->bitstream,
+                          &vtctx->allocated_size,
+                          vtctx->bitstream_size+size+4);
+    if (!tmp)
+        return AVERROR(ENOMEM);
+
+    vtctx->bitstream = tmp;
+
+    AV_WB32(vtctx->bitstream + vtctx->bitstream_size, size);
+    memcpy(vtctx->bitstream + vtctx->bitstream_size + 4, buffer, size);
+
+    vtctx->bitstream_size += size + 4;
+
+    return 0;
+}
+
+int ff_videotoolbox_uninit(AVCodecContext *avctx)
+{
+    VTContext *vtctx = avctx->internal->hwaccel_priv_data;
+    if (vtctx) {
+        av_freep(&vtctx->bitstream);
+        if (vtctx->frame)
+            CVPixelBufferRelease(vtctx->frame);
+    }
+
+    return 0;
+}
+
+#if CONFIG_VIDEOTOOLBOX
+static void videotoolbox_write_mp4_descr_length(PutByteContext *pb, int length)
+{
+    int i;
+    uint8_t b;
+
+    for (i = 3; i >= 0; i--) {
+        b = (length >> (i * 7)) & 0x7F;
+        if (i != 0)
+            b |= 0x80;
+
+        bytestream2_put_byteu(pb, b);
+    }
+}
+
+static CFDataRef videotoolbox_esds_extradata_create(AVCodecContext *avctx)
+{
+    CFDataRef data;
+    uint8_t *rw_extradata;
+    PutByteContext pb;
+    int full_size = 3 + 5 + 13 + 5 + avctx->extradata_size + 3;
+    // ES_DescrTag data + DecoderConfigDescrTag + data + DecSpecificInfoTag + size + SLConfigDescriptor
+    int config_size = 13 + 5 + avctx->extradata_size;
+    int s;
+
+    if (!(rw_extradata = av_mallocz(full_size + VIDEOTOOLBOX_ESDS_EXTRADATA_PADDING)))
+        return NULL;
+
+    bytestream2_init_writer(&pb, rw_extradata, full_size + VIDEOTOOLBOX_ESDS_EXTRADATA_PADDING);
+    bytestream2_put_byteu(&pb, 0);        // version
+    bytestream2_put_ne24(&pb, 0);         // flags
+
+    // elementary stream descriptor
+    bytestream2_put_byteu(&pb, 0x03);     // ES_DescrTag
+    videotoolbox_write_mp4_descr_length(&pb, full_size);
+    bytestream2_put_ne16(&pb, 0);         // esid
+    bytestream2_put_byteu(&pb, 0);        // stream priority (0-32)
+
+    // decoder configuration descriptor
+    bytestream2_put_byteu(&pb, 0x04);     // DecoderConfigDescrTag
+    videotoolbox_write_mp4_descr_length(&pb, config_size);
+    bytestream2_put_byteu(&pb, 32);       // object type indication. 32 = CODEC_ID_MPEG4
+    bytestream2_put_byteu(&pb, 0x11);     // stream type
+    bytestream2_put_ne24(&pb, 0);         // buffer size
+    bytestream2_put_ne32(&pb, 0);         // max bitrate
+    bytestream2_put_ne32(&pb, 0);         // avg bitrate
+
+    // decoder specific descriptor
+    bytestream2_put_byteu(&pb, 0x05);     ///< DecSpecificInfoTag
+    videotoolbox_write_mp4_descr_length(&pb, avctx->extradata_size);
+
+    bytestream2_put_buffer(&pb, avctx->extradata, avctx->extradata_size);
+
+    // SLConfigDescriptor
+    bytestream2_put_byteu(&pb, 0x06);     // SLConfigDescrTag
+    bytestream2_put_byteu(&pb, 0x01);     // length
+    bytestream2_put_byteu(&pb, 0x02);     //
+
+    s = bytestream2_size_p(&pb);
+
+    data = CFDataCreate(kCFAllocatorDefault, rw_extradata, s);
+
+    av_freep(&rw_extradata);
+    return data;
+}
+
+static CMSampleBufferRef videotoolbox_sample_buffer_create(CMFormatDescriptionRef fmt_desc,
+                                                           void *buffer,
+                                                           int size)
+{
+    OSStatus status;
+    CMBlockBufferRef  block_buf;
+    CMSampleBufferRef sample_buf;
+
+    block_buf  = NULL;
+    sample_buf = NULL;
+
+    status = CMBlockBufferCreateWithMemoryBlock(kCFAllocatorDefault,// structureAllocator
+                                                buffer,             // memoryBlock
+                                                size,               // blockLength
+                                                kCFAllocatorNull,   // blockAllocator
+                                                NULL,               // customBlockSource
+                                                0,                  // offsetToData
+                                                size,               // dataLength
+                                                0,                  // flags
+                                                &block_buf);
+
+    if (!status) {
+        status = CMSampleBufferCreate(kCFAllocatorDefault,  // allocator
+                                      block_buf,            // dataBuffer
+                                      TRUE,                 // dataReady
+                                      0,                    // makeDataReadyCallback
+                                      0,                    // makeDataReadyRefcon
+                                      fmt_desc,             // formatDescription
+                                      1,                    // numSamples
+                                      0,                    // numSampleTimingEntries
+                                      NULL,                 // sampleTimingArray
+                                      0,                    // numSampleSizeEntries
+                                      NULL,                 // sampleSizeArray
+                                      &sample_buf);
+    }
+
+    if (block_buf)
+        CFRelease(block_buf);
+
+    return sample_buf;
+}
+
+static void videotoolbox_decoder_callback(void *opaque,
+                                          void *sourceFrameRefCon,
+                                          OSStatus status,
+                                          VTDecodeInfoFlags flags,
+                                          CVImageBufferRef image_buffer,
+                                          CMTime pts,
+                                          CMTime duration)
+{
+    AVCodecContext *avctx = opaque;
+    VTContext *vtctx = avctx->internal->hwaccel_priv_data;
+
+    if (vtctx->frame) {
+        CVPixelBufferRelease(vtctx->frame);
+        vtctx->frame = NULL;
+    }
+
+    if (!image_buffer) {
+        av_log(NULL, AV_LOG_DEBUG, "vt decoder cb: output image buffer is null\n");
+        return;
+    }
+
+    vtctx->frame = CVPixelBufferRetain(image_buffer);
+}
+
+static OSStatus videotoolbox_session_decode_frame(AVCodecContext *avctx)
+{
+    OSStatus status;
+    CMSampleBufferRef sample_buf;
+    AVVideotoolboxContext *videotoolbox = avctx->hwaccel_context;
+    VTContext *vtctx = avctx->internal->hwaccel_priv_data;
+
+    sample_buf = videotoolbox_sample_buffer_create(videotoolbox->cm_fmt_desc,
+                                                   vtctx->bitstream,
+                                                   vtctx->bitstream_size);
+
+    if (!sample_buf)
+        return -1;
+
+    status = VTDecompressionSessionDecodeFrame(videotoolbox->session,
+                                               sample_buf,
+                                               0,       // decodeFlags
+                                               NULL,    // sourceFrameRefCon
+                                               0);      // infoFlagsOut
+    if (status == noErr)
+        status = VTDecompressionSessionWaitForAsynchronousFrames(videotoolbox->session);
+
+    CFRelease(sample_buf);
+
+    return status;
+}
+
+static int videotoolbox_common_end_frame(AVCodecContext *avctx, AVFrame *frame)
+{
+    int status;
+    AVVideotoolboxContext *videotoolbox = avctx->hwaccel_context;
+    VTContext *vtctx = avctx->internal->hwaccel_priv_data;
+
+    if (!videotoolbox->session || !vtctx->bitstream)
+        return AVERROR_INVALIDDATA;
+
+    status = videotoolbox_session_decode_frame(avctx);
+
+    if (status) {
+        av_log(avctx, AV_LOG_ERROR, "Failed to decode frame (%d)\n", status);
+        return AVERROR_UNKNOWN;
+    }
+
+    if (!vtctx->frame)
+        return AVERROR_UNKNOWN;
+
+    return ff_videotoolbox_buffer_create(vtctx, frame);
+}
+
+static int videotoolbox_h264_end_frame(AVCodecContext *avctx)
+{
+    H264Context *h = avctx->priv_data;
+    AVFrame *frame = h->cur_pic_ptr->f;
+
+    return videotoolbox_common_end_frame(avctx, frame);
+}
+
+static int videotoolbox_mpeg_start_frame(AVCodecContext *avctx,
+                                         const uint8_t *buffer,
+                                         uint32_t size)
+{
+    VTContext *vtctx = avctx->internal->hwaccel_priv_data;
+
+    return videotoolbox_buffer_copy(vtctx, buffer, size);
+}
+
+static int videotoolbox_mpeg_decode_slice(AVCodecContext *avctx,
+                                          const uint8_t *buffer,
+                                          uint32_t size)
+{
+    return 0;
+}
+
+static int videotoolbox_mpeg_end_frame(AVCodecContext *avctx)
+{
+    MpegEncContext *s = avctx->priv_data;
+    AVFrame *frame = s->current_picture_ptr->f;
+
+    return videotoolbox_common_end_frame(avctx, frame);
+}
+
+static CFDictionaryRef videotoolbox_decoder_config_create(CMVideoCodecType codec_type,
+                                                          AVCodecContext *avctx)
+{
+    CFMutableDictionaryRef config_info = CFDictionaryCreateMutable(kCFAllocatorDefault,
+                                                                   1,
+                                                                   &kCFTypeDictionaryKeyCallBacks,
+                                                                   &kCFTypeDictionaryValueCallBacks);
+
+    CFDictionarySetValue(config_info,
+                         kVTVideoDecoderSpecification_EnableHardwareAcceleratedVideoDecoder,
+                         kCFBooleanTrue);
+
+    if (avctx->extradata_size) {
+        CFMutableDictionaryRef avc_info;
+        CFDataRef data = NULL;
+
+        avc_info = CFDictionaryCreateMutable(kCFAllocatorDefault,
+                                             1,
+                                             &kCFTypeDictionaryKeyCallBacks,
+                                             &kCFTypeDictionaryValueCallBacks);
+
+        switch (codec_type) {
+        case kCMVideoCodecType_MPEG4Video :
+            data = videotoolbox_esds_extradata_create(avctx);
+            if (data)
+                CFDictionarySetValue(avc_info, CFSTR("esds"), data);
+            break;
+        case kCMVideoCodecType_H264 :
+            data = ff_videotoolbox_avcc_extradata_create(avctx);
+            if (data)
+                CFDictionarySetValue(avc_info, CFSTR("avcC"), data);
+            break;
+        default:
+            break;
+        }
+
+        CFDictionarySetValue(config_info,
+                kCMFormatDescriptionExtension_SampleDescriptionExtensionAtoms,
+                avc_info);
+
+        if (data)
+            CFRelease(data);
+
+        CFRelease(avc_info);
+    }
+    return config_info;
+}
+
+static CFDictionaryRef videotoolbox_buffer_attributes_create(int width,
+                                                             int height,
+                                                             OSType pix_fmt)
+{
+    CFMutableDictionaryRef buffer_attributes;
+    CFMutableDictionaryRef io_surface_properties;
+    CFNumberRef cv_pix_fmt;
+    CFNumberRef w;
+    CFNumberRef h;
+
+    w = CFNumberCreate(kCFAllocatorDefault, kCFNumberSInt32Type, &width);
+    h = CFNumberCreate(kCFAllocatorDefault, kCFNumberSInt32Type, &height);
+    cv_pix_fmt = CFNumberCreate(kCFAllocatorDefault, kCFNumberSInt32Type, &pix_fmt);
+
+    buffer_attributes = CFDictionaryCreateMutable(kCFAllocatorDefault,
+                                                  4,
+                                                  &kCFTypeDictionaryKeyCallBacks,
+                                                  &kCFTypeDictionaryValueCallBacks);
+    io_surface_properties = CFDictionaryCreateMutable(kCFAllocatorDefault,
+                                                      0,
+                                                      &kCFTypeDictionaryKeyCallBacks,
+                                                      &kCFTypeDictionaryValueCallBacks);
+
+    CFDictionarySetValue(buffer_attributes, kCVPixelBufferPixelFormatTypeKey, cv_pix_fmt);
+    CFDictionarySetValue(buffer_attributes, kCVPixelBufferIOSurfacePropertiesKey, io_surface_properties);
+    CFDictionarySetValue(buffer_attributes, kCVPixelBufferWidthKey, w);
+    CFDictionarySetValue(buffer_attributes, kCVPixelBufferHeightKey, h);
+
+    CFRelease(io_surface_properties);
+    CFRelease(cv_pix_fmt);
+    CFRelease(w);
+    CFRelease(h);
+
+    return buffer_attributes;
+}
+
+static CMVideoFormatDescriptionRef videotoolbox_format_desc_create(CMVideoCodecType codec_type,
+                                                                   CFDictionaryRef decoder_spec,
+                                                                   int width,
+                                                                   int height)
+{
+    CMFormatDescriptionRef cm_fmt_desc;
+    OSStatus status;
+
+    status = CMVideoFormatDescriptionCreate(kCFAllocatorDefault,
+                                            codec_type,
+                                            width,
+                                            height,
+                                            decoder_spec, // Dictionary of extension
+                                            &cm_fmt_desc);
+
+    if (status)
+        return NULL;
+
+    return cm_fmt_desc;
+}
+
+static int videotoolbox_default_init(AVCodecContext *avctx)
+{
+    AVVideotoolboxContext *videotoolbox = avctx->hwaccel_context;
+    OSStatus status;
+    VTDecompressionOutputCallbackRecord decoder_cb;
+    CFDictionaryRef decoder_spec;
+    CFDictionaryRef buf_attr;
+    int32_t pix_fmt;
+
+    if (!videotoolbox) {
+        av_log(avctx, AV_LOG_ERROR, "hwaccel context is not set\n");
+        return -1;
+    }
+
+    switch( avctx->codec_id ) {
+    case AV_CODEC_ID_H263 :
+        videotoolbox->cm_codec_type = kCMVideoCodecType_H263;
+        break;
+    case AV_CODEC_ID_H264 :
+        videotoolbox->cm_codec_type = kCMVideoCodecType_H264;
+        break;
+    case AV_CODEC_ID_MPEG1VIDEO :
+        videotoolbox->cm_codec_type = kCMVideoCodecType_MPEG1Video;
+        break;
+    case AV_CODEC_ID_MPEG2VIDEO :
+        videotoolbox->cm_codec_type = kCMVideoCodecType_MPEG2Video;
+        break;
+    case AV_CODEC_ID_MPEG4 :
+        videotoolbox->cm_codec_type = kCMVideoCodecType_MPEG4Video;
+        break;
+    default :
+        break;
+    }
+
+    pix_fmt = videotoolbox->cv_pix_fmt_type;
+
+    decoder_spec = videotoolbox_decoder_config_create(videotoolbox->cm_codec_type, avctx);
+
+    videotoolbox->cm_fmt_desc = videotoolbox_format_desc_create(videotoolbox->cm_codec_type,
+                                                                decoder_spec,
+                                                                avctx->width,
+                                                                avctx->height);
+    if (!videotoolbox->cm_fmt_desc) {
+        if (decoder_spec)
+            CFRelease(decoder_spec);
+
+        av_log(avctx, AV_LOG_ERROR, "format description creation failed\n");
+        return -1;
+    }
+
+    buf_attr = videotoolbox_buffer_attributes_create(avctx->width,
+                                                     avctx->height,
+                                                     videotoolbox->cv_pix_fmt_type);
+
+    decoder_cb.decompressionOutputCallback = videotoolbox_decoder_callback;
+    decoder_cb.decompressionOutputRefCon   = avctx;
+
+    status = VTDecompressionSessionCreate(NULL,                      // allocator
+                                          videotoolbox->cm_fmt_desc, // videoFormatDescription
+                                          decoder_spec,              // videoDecoderSpecification
+                                          buf_attr,                  // destinationImageBufferAttributes
+                                          &decoder_cb,               // outputCallback
+                                          &videotoolbox->session);   // decompressionSessionOut
+
+    if (decoder_spec)
+        CFRelease(decoder_spec);
+    if (buf_attr)
+        CFRelease(buf_attr);
+
+    switch (status) {
+    case kVTVideoDecoderNotAvailableNowErr:
+    case kVTVideoDecoderUnsupportedDataFormatErr:
+        return AVERROR(ENOSYS);
+    case kVTVideoDecoderMalfunctionErr:
+        return AVERROR(EINVAL);
+    case kVTVideoDecoderBadDataErr :
+        return AVERROR_INVALIDDATA;
+    case 0:
+        return 0;
+    default:
+        return AVERROR_UNKNOWN;
+    }
+}
+
+static void videotoolbox_default_free(AVCodecContext *avctx)
+{
+    AVVideotoolboxContext *videotoolbox = avctx->hwaccel_context;
+
+    if (videotoolbox) {
+        if (videotoolbox->cm_fmt_desc)
+            CFRelease(videotoolbox->cm_fmt_desc);
+
+        if (videotoolbox->session)
+            VTDecompressionSessionInvalidate(videotoolbox->session);
+    }
+}
+
+AVHWAccel ff_h263_videotoolbox_hwaccel = {
+    .name           = "h263_videotoolbox",
+    .type           = AVMEDIA_TYPE_VIDEO,
+    .id             = AV_CODEC_ID_H263,
+    .pix_fmt        = AV_PIX_FMT_VIDEOTOOLBOX,
+    .alloc_frame    = ff_videotoolbox_alloc_frame,
+    .start_frame    = videotoolbox_mpeg_start_frame,
+    .decode_slice   = videotoolbox_mpeg_decode_slice,
+    .end_frame      = videotoolbox_mpeg_end_frame,
+    .uninit         = ff_videotoolbox_uninit,
+    .priv_data_size = sizeof(VTContext),
+};
+
+AVHWAccel ff_h264_videotoolbox_hwaccel = {
+    .name           = "h264_videotoolbox",
+    .type           = AVMEDIA_TYPE_VIDEO,
+    .id             = AV_CODEC_ID_H264,
+    .pix_fmt        = AV_PIX_FMT_VIDEOTOOLBOX,
+    .alloc_frame    = ff_videotoolbox_alloc_frame,
+    .start_frame    = ff_videotoolbox_h264_start_frame,
+    .decode_slice   = ff_videotoolbox_h264_decode_slice,
+    .end_frame      = videotoolbox_h264_end_frame,
+    .uninit         = ff_videotoolbox_uninit,
+    .priv_data_size = sizeof(VTContext),
+};
+
+AVHWAccel ff_mpeg1_videotoolbox_hwaccel = {
+    .name           = "mpeg1_videotoolbox",
+    .type           = AVMEDIA_TYPE_VIDEO,
+    .id             = AV_CODEC_ID_MPEG1VIDEO,
+    .pix_fmt        = AV_PIX_FMT_VIDEOTOOLBOX,
+    .alloc_frame    = ff_videotoolbox_alloc_frame,
+    .start_frame    = videotoolbox_mpeg_start_frame,
+    .decode_slice   = videotoolbox_mpeg_decode_slice,
+    .end_frame      = videotoolbox_mpeg_end_frame,
+    .uninit         = ff_videotoolbox_uninit,
+    .priv_data_size = sizeof(VTContext),
+};
+
+AVHWAccel ff_mpeg2_videotoolbox_hwaccel = {
+    .name           = "mpeg2_videotoolbox",
+    .type           = AVMEDIA_TYPE_VIDEO,
+    .id             = AV_CODEC_ID_MPEG2VIDEO,
+    .pix_fmt        = AV_PIX_FMT_VIDEOTOOLBOX,
+    .alloc_frame    = ff_videotoolbox_alloc_frame,
+    .start_frame    = videotoolbox_mpeg_start_frame,
+    .decode_slice   = videotoolbox_mpeg_decode_slice,
+    .end_frame      = videotoolbox_mpeg_end_frame,
+    .uninit         = ff_videotoolbox_uninit,
+    .priv_data_size = sizeof(VTContext),
+};
+
+AVHWAccel ff_mpeg4_videotoolbox_hwaccel = {
+    .name           = "mpeg4_videotoolbox",
+    .type           = AVMEDIA_TYPE_VIDEO,
+    .id             = AV_CODEC_ID_MPEG4,
+    .pix_fmt        = AV_PIX_FMT_VIDEOTOOLBOX,
+    .alloc_frame    = ff_videotoolbox_alloc_frame,
+    .start_frame    = videotoolbox_mpeg_start_frame,
+    .decode_slice   = videotoolbox_mpeg_decode_slice,
+    .end_frame      = videotoolbox_mpeg_end_frame,
+    .uninit         = ff_videotoolbox_uninit,
+    .priv_data_size = sizeof(VTContext),
+};
+
+AVVideotoolboxContext *av_videotoolbox_alloc_context(void)
+{
+    AVVideotoolboxContext *ret = av_mallocz(sizeof(*ret));
+
+    if (ret) {
+        ret->output_callback = videotoolbox_decoder_callback;
+        ret->cv_pix_fmt_type = kCVPixelFormatType_420YpCbCr8BiPlanarVideoRange;
+    }
+
+    return ret;
+}
+
+int av_videotoolbox_default_init(AVCodecContext *avctx)
+{
+    return av_videotoolbox_default_init2(avctx, NULL);
+}
+
+int av_videotoolbox_default_init2(AVCodecContext *avctx, AVVideotoolboxContext *vtctx)
+{
+    avctx->hwaccel_context = vtctx ?: av_videotoolbox_alloc_context();
+    if (!avctx->hwaccel_context)
+        return AVERROR(ENOMEM);
+    return videotoolbox_default_init(avctx);
+}
+
+void av_videotoolbox_default_free(AVCodecContext *avctx)
+{
+
+    videotoolbox_default_free(avctx);
+    av_freep(&avctx->hwaccel_context);
+}
+#endif /* CONFIG_VIDEOTOOLBOX */