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 <stdio.h>
32 
33 #include <libavformat/avformat.h>
34 #include <libavformat/avio.h>
35 
36 #include <libavcodec/avcodec.h>
37 
38 #include <libavutil/buffer.h>
39 #include <libavutil/error.h>
40 #include <libavutil/hwcontext.h>
42 #include <libavutil/mem.h>
43 
44 static int get_format(AVCodecContext *avctx, const enum AVPixelFormat *pix_fmts)
45 {
46  while (*pix_fmts != AV_PIX_FMT_NONE) {
47  if (*pix_fmts == AV_PIX_FMT_QSV) {
48  return AV_PIX_FMT_QSV;
49  }
50 
51  pix_fmts++;
52  }
53 
54  fprintf(stderr, "The QSV pixel format not offered in get_format()\n");
55 
56  return AV_PIX_FMT_NONE;
57 }
58 
60  AVFrame *frame, AVFrame *sw_frame,
61  AVPacket *pkt, AVIOContext *output_ctx)
62 {
63  int ret = 0;
64 
66  if (ret < 0) {
67  fprintf(stderr, "Error during decoding\n");
68  return ret;
69  }
70 
71  while (ret >= 0) {
72  int i, j;
73 
75  if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF)
76  break;
77  else if (ret < 0) {
78  fprintf(stderr, "Error during decoding\n");
79  return ret;
80  }
81 
82  /* A real program would do something useful with the decoded frame here.
83  * We just retrieve the raw data and write it to a file, which is rather
84  * useless but pedagogic. */
85  ret = av_hwframe_transfer_data(sw_frame, frame, 0);
86  if (ret < 0) {
87  fprintf(stderr, "Error transferring the data to system memory\n");
88  goto fail;
89  }
90 
91  for (i = 0; i < FF_ARRAY_ELEMS(sw_frame->data) && sw_frame->data[i]; i++)
92  for (j = 0; j < (sw_frame->height >> (i > 0)); j++)
93  avio_write(output_ctx, sw_frame->data[i] + j * sw_frame->linesize[i], sw_frame->width);
94 
95 fail:
96  av_frame_unref(sw_frame);
98 
99  if (ret < 0)
100  return ret;
101  }
102 
103  return 0;
104 }
105 
106 int main(int argc, char **argv)
107 {
108  AVFormatContext *input_ctx = NULL;
111  const AVCodec *decoder;
112 
113  AVPacket *pkt = NULL;
114  AVFrame *frame = NULL, *sw_frame = NULL;
115 
116  AVIOContext *output_ctx = NULL;
117 
118  int ret, i;
119 
120  AVBufferRef *device_ref = NULL;
121 
122  if (argc < 3) {
123  fprintf(stderr, "Usage: %s <input file> <output file>\n", argv[0]);
124  return 1;
125  }
126 
127  /* open the input file */
128  ret = avformat_open_input(&input_ctx, argv[1], NULL, NULL);
129  if (ret < 0) {
130  fprintf(stderr, "Cannot open input file '%s': ", argv[1]);
131  goto finish;
132  }
133 
134  /* find the first H.264 video stream */
135  for (i = 0; i < input_ctx->nb_streams; i++) {
136  AVStream *st = input_ctx->streams[i];
137 
138  if (st->codecpar->codec_id == AV_CODEC_ID_H264 && !video_st)
139  video_st = st;
140  else
141  st->discard = AVDISCARD_ALL;
142  }
143  if (!video_st) {
144  fprintf(stderr, "No H.264 video stream in the input file\n");
145  goto finish;
146  }
147 
148  /* open the hardware device */
150  "auto", NULL, 0);
151  if (ret < 0) {
152  fprintf(stderr, "Cannot open the hardware device\n");
153  goto finish;
154  }
155 
156  /* initialize the decoder */
158  if (!decoder) {
159  fprintf(stderr, "The QSV decoder is not present in libavcodec\n");
160  goto finish;
161  }
162 
164  if (!decoder_ctx) {
165  ret = AVERROR(ENOMEM);
166  goto finish;
167  }
172  if (!decoder_ctx->extradata) {
173  ret = AVERROR(ENOMEM);
174  goto finish;
175  }
179  }
180 
181 
182  decoder_ctx->hw_device_ctx = av_buffer_ref(device_ref);
184 
186  if (ret < 0) {
187  fprintf(stderr, "Error opening the decoder: ");
188  goto finish;
189  }
190 
191  /* open the output stream */
192  ret = avio_open(&output_ctx, argv[2], AVIO_FLAG_WRITE);
193  if (ret < 0) {
194  fprintf(stderr, "Error opening the output context: ");
195  goto finish;
196  }
197 
198  frame = av_frame_alloc();
199  sw_frame = av_frame_alloc();
200  pkt = av_packet_alloc();
201  if (!frame || !sw_frame || !pkt) {
202  ret = AVERROR(ENOMEM);
203  goto finish;
204  }
205 
206  /* actual decoding */
207  while (ret >= 0) {
208  ret = av_read_frame(input_ctx, pkt);
209  if (ret < 0)
210  break;
211 
212  if (pkt->stream_index == video_st->index)
213  ret = decode_packet(decoder_ctx, frame, sw_frame, pkt, output_ctx);
214 
216  }
217 
218  /* flush the decoder */
219  ret = decode_packet(decoder_ctx, frame, sw_frame, NULL, output_ctx);
220 
221 finish:
222  if (ret < 0) {
223  char buf[1024];
224  av_strerror(ret, buf, sizeof(buf));
225  fprintf(stderr, "%s\n", buf);
226  }
227 
228  avformat_close_input(&input_ctx);
229 
231  av_frame_free(&sw_frame);
233 
235 
236  av_buffer_unref(&device_ref);
237 
238  avio_close(output_ctx);
239 
240  return ret;
241 }
av_packet_unref
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: packet.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:787
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:814
get_format
static int get_format(AVCodecContext *avctx, const enum AVPixelFormat *pix_fmts)
Definition: qsv_decode.c:44
av_frame_free
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:160
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:374
AVFormatContext::streams
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1323
AVFrame::width
int width
Definition: frame.h:446
avio_open
int avio_open(AVIOContext **s, const char *filename, int flags)
Create and initialize a AVIOContext for accessing the resource indicated by url.
Definition: avio.c:497
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:1538
av_packet_free
void av_packet_free(AVPacket **pkt)
Free the packet, if the packet is reference counted, it will be unreferenced first.
Definition: packet.c:74
AVFrame::data
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:395
avformat_close_input
void avformat_close_input(AVFormatContext **s)
Close an opened input AVFormatContext.
Definition: demux.c:363
decoder
static const chunk_decoder decoder[8]
Definition: dfa.c:331
finish
static void finish(void)
Definition: movenc.c:373
fail
#define fail()
Definition: checkasm.h:185
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:109
av_frame_alloc
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:148
pkt
AVPacket * pkt
Definition: movenc.c:60
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:215
AVCodecContext::extradata_size
int extradata_size
Definition: avcodec.h:524
avcodec_alloc_context3
AVCodecContext * avcodec_alloc_context3(const AVCodec *codec)
Allocate an AVCodecContext and set its fields to default values.
Definition: options.c:149
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:698
pix_fmts
static enum AVPixelFormat pix_fmts[]
Definition: libkvazaar.c:304
AVIO_FLAG_WRITE
#define AVIO_FLAG_WRITE
write-only
Definition: avio.h:618
AV_CODEC_ID_H264
@ AV_CODEC_ID_H264
Definition: codec_id.h:79
AVCodecContext::codec_id
enum AVCodecID codec_id
Definition: avcodec.h:455
AVDISCARD_ALL
@ AVDISCARD_ALL
discard all
Definition: defs.h:220
AVFormatContext
Format I/O context.
Definition: avformat.h:1255
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:766
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:993
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:164
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:142
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:1311
AVIOContext
Bytestream IO Context.
Definition: avio.h:160
main
int main(int argc, char **argv)
Definition: qsv_decode.c:106
avio.h
video_st
AVStream * video_st
Definition: movenc.c:61
buffer.h
avio_write
void avio_write(AVIOContext *s, const unsigned char *buf, int size)
Definition: aviobuf.c:201
av_packet_alloc
AVPacket * av_packet_alloc(void)
Allocate an AVPacket and set its fields to default values.
Definition: packet.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:59
avcodec_send_packet
int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt)
Supply raw packet data as input to a decoder.
Definition: decode.c:696
hwcontext_qsv.h
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:256
AVCodecContext::extradata
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:523
av_frame_unref
void av_frame_unref(AVFrame *frame)
Unreference all the buffers referenced by frame and reset the frame fields.
Definition: frame.c:606
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:256
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:1497
avcodec.h
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:743
frame
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
Definition: filter_design.txt:264
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:600
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:433
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:446
AVStream::index
int index
stream index in AVFormatContext
Definition: avformat.h:749
AV_PIX_FMT_NONE
@ AV_PIX_FMT_NONE
Definition: pixfmt.h:72
AVPacket::stream_index
int stream_index
Definition: packet.h:522
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:497
hwcontext.h
avio_close
int avio_close(AVIOContext *s)
Close the resource accessed by the AVIOContext s and free it.
Definition: avio.c:616
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:419
decoder_ctx
static AVCodecContext * decoder_ctx
Definition: qsv_transcode.c:48