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FFmpeg/libavcodec/videotoolbox.c
wm4 16aac9a359 avcodec/videotoolbox: fix decoding of some h264 bitstreams
This affects Annex B streams (such as demuxed from .ts and others). It
also handles the format change in reinit-large_420_8-to-small_420_8.h264
correctly.

Instead of passing through the extradata, create it on the fly it from
the currently active SPS and PPS. Since reconstructing the PPS and SPS
NALs would be very complicated and verbose, we use the NALs as they
originally appeared in the bitstream.

The code for writing the extradata is somewhat derived from
libavformat/avc.c, but it's small and different enough that sharing it
is not really worth it.
2015-10-02 19:09:16 +02:00

700 lines
24 KiB
C

/*
* 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_RequireHardwareAcceleratedVideoDecoder
# define kVTVideoDecoderSpecification_RequireHardwareAcceleratedVideoDecoder CFSTR("RequireHardwareAcceleratedVideoDecoder")
#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;
}
#define AV_W8(p, v) *(p) = (v)
CFDataRef ff_videotoolbox_avcc_extradata_create(AVCodecContext *avctx)
{
H264Context *h = avctx->priv_data;
CFDataRef data = NULL;
uint8_t *p;
int vt_extradata_size = 6 + 3 + h->sps.data_size + 4 + h->pps.data_size;
uint8_t *vt_extradata = av_malloc(vt_extradata_size);
if (!vt_extradata)
return NULL;
p = vt_extradata;
AV_W8(p + 0, 1); /* version */
AV_W8(p + 1, h->sps.data[0]); /* profile */
AV_W8(p + 2, h->sps.data[1]); /* profile compat */
AV_W8(p + 3, h->sps.data[2]); /* level */
AV_W8(p + 4, 0xff); /* 6 bits reserved (111111) + 2 bits nal size length - 3 (11) */
AV_W8(p + 5, 0xe1); /* 3 bits reserved (111) + 5 bits number of sps (00001) */
AV_WB16(p + 6, h->sps.data_size + 1);
AV_W8(p + 8, NAL_SPS | (3 << 5)); // NAL unit header
memcpy(p + 9, h->sps.data, h->sps.data_size);
p += 9 + h->sps.data_size;
AV_W8(p + 0, 1); /* number of pps */
AV_WB16(p + 1, h->pps.data_size + 1);
AV_W8(p + 3, NAL_PPS | (3 << 5)); // NAL unit header
memcpy(p + 4, h->pps.data, h->pps.data_size);
p += 4 + h->pps.data_size;
av_assert0(p - vt_extradata == vt_extradata_size);
data = CFDataCreate(kCFAllocatorDefault, vt_extradata, vt_extradata_size);
av_free(vt_extradata);
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 = AV_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_RequireHardwareAcceleratedVideoDecoder,
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;
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;
}
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 */