FFmpeg
qsv_decode.c
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1 /*
2  * Copyright (c) 2015 Anton Khirnov
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a copy
5  * of this software and associated documentation files (the "Software"), to deal
6  * in the Software without restriction, including without limitation the rights
7  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
8  * copies of the Software, and to permit persons to whom the Software is
9  * furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice shall be included in
12  * all copies or substantial portions of the Software.
13  *
14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
17  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
18  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
19  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
20  * THE SOFTWARE.
21  */
22 
23 /**
24  * @file Intel QSV-accelerated H.264 decoding API usage example
25  * @example qsv_decode.c
26  *
27  * Perform QSV-accelerated H.264 decoding with output frames in the
28  * GPU video surfaces, write the decoded frames to an output file.
29  */
30 
31 #include "config.h"
32 
33 #include <stdio.h>
34 
35 #include "libavformat/avformat.h"
36 #include "libavformat/avio.h"
37 
38 #include "libavcodec/avcodec.h"
39 
40 #include "libavutil/buffer.h"
41 #include "libavutil/error.h"
42 #include "libavutil/hwcontext.h"
44 #include "libavutil/mem.h"
45 
46 static int get_format(AVCodecContext *avctx, const enum AVPixelFormat *pix_fmts)
47 {
48  while (*pix_fmts != AV_PIX_FMT_NONE) {
49  if (*pix_fmts == AV_PIX_FMT_QSV) {
50  return AV_PIX_FMT_QSV;
51  }
52 
53  pix_fmts++;
54  }
55 
56  fprintf(stderr, "The QSV pixel format not offered in get_format()\n");
57 
58  return AV_PIX_FMT_NONE;
59 }
60 
62  AVFrame *frame, AVFrame *sw_frame,
63  AVPacket *pkt, AVIOContext *output_ctx)
64 {
65  int ret = 0;
66 
68  if (ret < 0) {
69  fprintf(stderr, "Error during decoding\n");
70  return ret;
71  }
72 
73  while (ret >= 0) {
74  int i, j;
75 
77  if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF)
78  break;
79  else if (ret < 0) {
80  fprintf(stderr, "Error during decoding\n");
81  return ret;
82  }
83 
84  /* A real program would do something useful with the decoded frame here.
85  * We just retrieve the raw data and write it to a file, which is rather
86  * useless but pedagogic. */
87  ret = av_hwframe_transfer_data(sw_frame, frame, 0);
88  if (ret < 0) {
89  fprintf(stderr, "Error transferring the data to system memory\n");
90  goto fail;
91  }
92 
93  for (i = 0; i < FF_ARRAY_ELEMS(sw_frame->data) && sw_frame->data[i]; i++)
94  for (j = 0; j < (sw_frame->height >> (i > 0)); j++)
95  avio_write(output_ctx, sw_frame->data[i] + j * sw_frame->linesize[i], sw_frame->width);
96 
97 fail:
98  av_frame_unref(sw_frame);
100 
101  if (ret < 0)
102  return ret;
103  }
104 
105  return 0;
106 }
107 
108 int main(int argc, char **argv)
109 {
110  AVFormatContext *input_ctx = NULL;
113  const AVCodec *decoder;
114 
115  AVPacket *pkt = NULL;
116  AVFrame *frame = NULL, *sw_frame = NULL;
117 
118  AVIOContext *output_ctx = NULL;
119 
120  int ret, i;
121 
122  AVBufferRef *device_ref = NULL;
123 
124  if (argc < 3) {
125  fprintf(stderr, "Usage: %s <input file> <output file>\n", argv[0]);
126  return 1;
127  }
128 
129  /* open the input file */
130  ret = avformat_open_input(&input_ctx, argv[1], NULL, NULL);
131  if (ret < 0) {
132  fprintf(stderr, "Cannot open input file '%s': ", argv[1]);
133  goto finish;
134  }
135 
136  /* find the first H.264 video stream */
137  for (i = 0; i < input_ctx->nb_streams; i++) {
138  AVStream *st = input_ctx->streams[i];
139 
140  if (st->codecpar->codec_id == AV_CODEC_ID_H264 && !video_st)
141  video_st = st;
142  else
143  st->discard = AVDISCARD_ALL;
144  }
145  if (!video_st) {
146  fprintf(stderr, "No H.264 video stream in the input file\n");
147  goto finish;
148  }
149 
150  /* open the hardware device */
152  "auto", NULL, 0);
153  if (ret < 0) {
154  fprintf(stderr, "Cannot open the hardware device\n");
155  goto finish;
156  }
157 
158  /* initialize the decoder */
160  if (!decoder) {
161  fprintf(stderr, "The QSV decoder is not present in libavcodec\n");
162  goto finish;
163  }
164 
166  if (!decoder_ctx) {
167  ret = AVERROR(ENOMEM);
168  goto finish;
169  }
174  if (!decoder_ctx->extradata) {
175  ret = AVERROR(ENOMEM);
176  goto finish;
177  }
181  }
182 
183 
184  decoder_ctx->hw_device_ctx = av_buffer_ref(device_ref);
186 
188  if (ret < 0) {
189  fprintf(stderr, "Error opening the decoder: ");
190  goto finish;
191  }
192 
193  /* open the output stream */
194  ret = avio_open(&output_ctx, argv[2], AVIO_FLAG_WRITE);
195  if (ret < 0) {
196  fprintf(stderr, "Error opening the output context: ");
197  goto finish;
198  }
199 
200  frame = av_frame_alloc();
201  sw_frame = av_frame_alloc();
202  pkt = av_packet_alloc();
203  if (!frame || !sw_frame || !pkt) {
204  ret = AVERROR(ENOMEM);
205  goto finish;
206  }
207 
208  /* actual decoding */
209  while (ret >= 0) {
210  ret = av_read_frame(input_ctx, pkt);
211  if (ret < 0)
212  break;
213 
214  if (pkt->stream_index == video_st->index)
215  ret = decode_packet(decoder_ctx, frame, sw_frame, pkt, output_ctx);
216 
218  }
219 
220  /* flush the decoder */
221  ret = decode_packet(decoder_ctx, frame, sw_frame, NULL, output_ctx);
222 
223 finish:
224  if (ret < 0) {
225  char buf[1024];
226  av_strerror(ret, buf, sizeof(buf));
227  fprintf(stderr, "%s\n", buf);
228  }
229 
230  avformat_close_input(&input_ctx);
231 
233  av_frame_free(&sw_frame);
235 
237 
238  av_buffer_unref(&device_ref);
239 
240  avio_close(output_ctx);
241 
242  return ret;
243 }
av_packet_unref
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:427
AVCodec
AVCodec.
Definition: codec.h:187
AVCodecParameters::extradata
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: codec_par.h:69
AVPixelFormat
AVPixelFormat
Pixel format.
Definition: pixfmt.h:71
AVERROR
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later. That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another. Frame references ownership and permissions
AVCodecContext::get_format
enum AVPixelFormat(* get_format)(struct AVCodecContext *s, const enum AVPixelFormat *fmt)
Callback to negotiate the pixel format.
Definition: avcodec.h:716
avio_close
int avio_close(AVIOContext *s)
Close the resource accessed by the AVIOContext s and free it.
Definition: aviobuf.c:1335
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:57
AVStream::discard
enum AVDiscard discard
Selects which packets can be discarded at will and do not need to be demuxed.
Definition: avformat.h:912
get_format
static int get_format(AVCodecContext *avctx, const enum AVPixelFormat *pix_fmts)
Definition: qsv_decode.c:46
av_frame_free
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:100
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:340
AVFormatContext::streams
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1431
AVFrame::width
int width
Definition: frame.h:412
av_buffer_ref
AVBufferRef * av_buffer_ref(const AVBufferRef *buf)
Create a new reference to an AVBuffer.
Definition: buffer.c:103
av_read_frame
int av_read_frame(AVFormatContext *s, AVPacket *pkt)
Return the next frame of a stream.
Definition: demux.c:1558
av_packet_free
void av_packet_free(AVPacket **pkt)
Free the packet, if the packet is reference counted, it will be unreferenced first.
Definition: avpacket.c:74
AVFrame::data
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:361
avformat_close_input
void avformat_close_input(AVFormatContext **s)
Close an opened input AVFormatContext.
Definition: demux.c:374
decoder
static const chunk_decoder decoder[8]
Definition: dfa.c:331
finish
static void finish(void)
Definition: movenc.c:342
fail
#define fail()
Definition: checkasm.h:179
av_strerror
int av_strerror(int errnum, char *errbuf, size_t errbuf_size)
Put a description of the AVERROR code errnum in errbuf.
Definition: error.c:108
av_frame_alloc
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:88
pkt
AVPacket * pkt
Definition: movenc.c:59
FF_ARRAY_ELEMS
#define FF_ARRAY_ELEMS(a)
Definition: sinewin_tablegen.c:29
avformat_open_input
int avformat_open_input(AVFormatContext **ps, const char *url, const AVInputFormat *fmt, AVDictionary **options)
Open an input stream and read the header.
Definition: demux.c:226
AVCodecContext::extradata_size
int extradata_size
Definition: avcodec.h:547
avcodec_alloc_context3
AVCodecContext * avcodec_alloc_context3(const AVCodec *codec)
Allocate an AVCodecContext and set its fields to default values.
Definition: options.c:154
avcodec_receive_frame
int attribute_align_arg avcodec_receive_frame(AVCodecContext *avctx, AVFrame *frame)
Return decoded output data from a decoder or encoder (when the AV_CODEC_FLAG_RECON_FRAME flag is used...
Definition: avcodec.c:715
pix_fmts
static enum AVPixelFormat pix_fmts[]
Definition: libkvazaar.c:304
AVIO_FLAG_WRITE
#define AVIO_FLAG_WRITE
write-only
Definition: avio.h:637
AV_CODEC_ID_H264
@ AV_CODEC_ID_H264
Definition: codec_id.h:79
frame
static AVFrame * frame
Definition: demux_decode.c:54
AVCodecContext::codec_id
enum AVCodecID codec_id
Definition: avcodec.h:455
AVDISCARD_ALL
@ AVDISCARD_ALL
discard all
Definition: defs.h:219
AVFormatContext
Format I/O context.
Definition: avformat.h:1363
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:864
NULL
#define NULL
Definition: coverity.c:32
avcodec_find_decoder_by_name
const AVCodec * avcodec_find_decoder_by_name(const char *name)
Find a registered decoder with the specified name.
Definition: allcodecs.c:1009
av_buffer_unref
void av_buffer_unref(AVBufferRef **buf)
Free a given reference and automatically free the buffer if there are no more references to it.
Definition: buffer.c:139
avcodec_free_context
void avcodec_free_context(AVCodecContext **avctx)
Free the codec context and everything associated with it and write NULL to the provided pointer.
Definition: options.c:169
avcodec_open2
int attribute_align_arg avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options)
Initialize the AVCodecContext to use the given AVCodec.
Definition: avcodec.c:128
AV_PIX_FMT_QSV
@ AV_PIX_FMT_QSV
HW acceleration through QSV, data[3] contains a pointer to the mfxFrameSurface1 structure.
Definition: pixfmt.h:247
error.h
AVCodecParameters::extradata_size
int extradata_size
Size of the extradata content in bytes.
Definition: codec_par.h:73
AVFormatContext::nb_streams
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
Definition: avformat.h:1419
AVIOContext
Bytestream IO Context.
Definition: avio.h:166
main
int main(int argc, char **argv)
Definition: qsv_decode.c:108
avio.h
video_st
AVStream * video_st
Definition: movenc.c:60
buffer.h
avio_write
void avio_write(AVIOContext *s, const unsigned char *buf, int size)
Definition: aviobuf.c:248
av_packet_alloc
AVPacket * av_packet_alloc(void)
Allocate an AVPacket and set its fields to default values.
Definition: avpacket.c:63
decode_packet
static int decode_packet(AVCodecContext *decoder_ctx, AVFrame *frame, AVFrame *sw_frame, AVPacket *pkt, AVIOContext *output_ctx)
Definition: qsv_decode.c:61
avcodec_send_packet
int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt)
Supply raw packet data as input to a decoder.
Definition: decode.c:709
hwcontext_qsv.h
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:255
AVCodecContext::extradata
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:546
av_frame_unref
void av_frame_unref(AVFrame *frame)
Unreference all the buffers referenced by frame and reset the frame fields.
Definition: frame.c:622
av_mallocz
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
Definition: mem.c:254
AVCodecContext::hw_device_ctx
AVBufferRef * hw_device_ctx
A reference to the AVHWDeviceContext describing the device which will be used by a hardware encoder/d...
Definition: avcodec.h:1985
avcodec.h
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:841
av_hwdevice_ctx_create
int av_hwdevice_ctx_create(AVBufferRef **pdevice_ref, enum AVHWDeviceType type, const char *device, AVDictionary *opts, int flags)
Open a device of the specified type and create an AVHWDeviceContext for it.
Definition: hwcontext.c:618
avformat.h
AV_INPUT_BUFFER_PADDING_SIZE
#define AV_INPUT_BUFFER_PADDING_SIZE
Definition: defs.h:40
av_hwframe_transfer_data
int av_hwframe_transfer_data(AVFrame *dst, const AVFrame *src, int flags)
Copy data to or from a hw surface.
Definition: hwcontext.c:451
AV_HWDEVICE_TYPE_QSV
@ AV_HWDEVICE_TYPE_QSV
Definition: hwcontext.h:33
AVCodecContext
main external API structure.
Definition: avcodec.h:445
AVFrame::height
int height
Definition: frame.h:412
AVStream::index
int index
stream index in AVFormatContext
Definition: avformat.h:847
AV_PIX_FMT_NONE
@ AV_PIX_FMT_NONE
Definition: pixfmt.h:72
avio_open
int avio_open(AVIOContext **s, const char *url, int flags)
Create and initialize a AVIOContext for accessing the resource indicated by url.
Definition: aviobuf.c:1303
AVPacket::stream_index
int stream_index
Definition: packet.h:524
mem.h
AVBufferRef
A reference to a data buffer.
Definition: buffer.h:82
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:55
AVPacket
This structure stores compressed data.
Definition: packet.h:499
hwcontext.h
AVFrame::linesize
int linesize[AV_NUM_DATA_POINTERS]
For video, a positive or negative value, which is typically indicating the size in bytes of each pict...
Definition: frame.h:385
decoder_ctx
static AVCodecContext * decoder_ctx
Definition: qsv_transcode.c:47