FFmpeg
api-h264-test.c
Go to the documentation of this file.
1 /*
2  * Copyright (c) 2015 Ludmila Glinskih
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  * H264 codec test.
25  */
26 
27 #include "libavutil/adler32.h"
28 #include "libavcodec/avcodec.h"
29 #include "libavformat/avformat.h"
30 #include "libavutil/imgutils.h"
31 #include "libavutil/timestamp.h"
32 
33 static int video_decode_example(const char *input_filename)
34 {
35  const AVCodec *codec = NULL;
37  AVCodecParameters *origin_par = NULL;
38  AVFrame *fr = NULL;
39  uint8_t *byte_buffer = NULL;
40  AVPacket *pkt;
42  int number_of_written_bytes;
43  int video_stream;
44  int byte_buffer_size;
45  int i = 0;
46  int result;
47 
49  if (result < 0) {
50  av_log(NULL, AV_LOG_ERROR, "Can't open file\n");
51  return result;
52  }
53 
55  if (result < 0) {
56  av_log(NULL, AV_LOG_ERROR, "Can't get stream info\n");
57  return result;
58  }
59 
61  if (video_stream < 0) {
62  av_log(NULL, AV_LOG_ERROR, "Can't find video stream in input file\n");
63  return -1;
64  }
65 
66  origin_par = fmt_ctx->streams[video_stream]->codecpar;
67 
68  codec = avcodec_find_decoder(origin_par->codec_id);
69  if (!codec) {
70  av_log(NULL, AV_LOG_ERROR, "Can't find decoder\n");
71  return -1;
72  }
73 
74  ctx = avcodec_alloc_context3(codec);
75  if (!ctx) {
76  av_log(NULL, AV_LOG_ERROR, "Can't allocate decoder context\n");
77  return AVERROR(ENOMEM);
78  }
79 
81  if (result) {
82  av_log(NULL, AV_LOG_ERROR, "Can't copy decoder context\n");
83  return result;
84  }
85 
86  result = avcodec_open2(ctx, codec, NULL);
87  if (result < 0) {
88  av_log(ctx, AV_LOG_ERROR, "Can't open decoder\n");
89  return result;
90  }
91 
92  fr = av_frame_alloc();
93  if (!fr) {
94  av_log(NULL, AV_LOG_ERROR, "Can't allocate frame\n");
95  return AVERROR(ENOMEM);
96  }
97 
98  pkt = av_packet_alloc();
99  if (!pkt) {
100  av_log(NULL, AV_LOG_ERROR, "Cannot allocate packet\n");
101  return AVERROR(ENOMEM);
102  }
103 
104  byte_buffer_size = av_image_get_buffer_size(ctx->pix_fmt, ctx->width, ctx->height, 16);
105  byte_buffer = av_malloc(byte_buffer_size);
106  if (!byte_buffer) {
107  av_log(NULL, AV_LOG_ERROR, "Can't allocate buffer\n");
108  return AVERROR(ENOMEM);
109  }
110 
112  i = 0;
113 
114  result = 0;
115  while (result >= 0) {
117  if (result >= 0 && pkt->stream_index != video_stream) {
119  continue;
120  }
121 
122  if (result < 0)
124  else {
125  if (pkt->pts == AV_NOPTS_VALUE)
126  pkt->pts = pkt->dts = i;
128  }
130 
131  if (result < 0) {
132  av_log(NULL, AV_LOG_ERROR, "Error submitting a packet for decoding\n");
133  return result;
134  }
135 
136  while (result >= 0) {
138  if (result == AVERROR_EOF)
139  goto finish;
140  else if (result == AVERROR(EAGAIN)) {
141  result = 0;
142  break;
143  } else if (result < 0) {
144  av_log(NULL, AV_LOG_ERROR, "Error decoding frame\n");
145  return result;
146  }
147 
148  number_of_written_bytes = av_image_copy_to_buffer(byte_buffer, byte_buffer_size,
149  (const uint8_t* const *)fr->data, (const int*) fr->linesize,
150  ctx->pix_fmt, ctx->width, ctx->height, 1);
151  if (number_of_written_bytes < 0) {
152  av_log(NULL, AV_LOG_ERROR, "Can't copy image to buffer\n");
153  av_frame_unref(fr);
154  return number_of_written_bytes;
155  }
156  printf("%d, %s, %s, %8"PRId64", %8d, 0x%08"PRIx32"\n", video_stream,
157  av_ts2str(fr->pts), av_ts2str(fr->pkt_dts), fr->pkt_duration,
158  number_of_written_bytes, av_adler32_update(0, (const uint8_t*)byte_buffer, number_of_written_bytes));
159 
160  av_frame_unref(fr);
161  }
162  i++;
163  }
164 
165 finish:
167  av_frame_free(&fr);
170  av_freep(&byte_buffer);
171  return 0;
172 }
173 
174 int main(int argc, char **argv)
175 {
176  if (argc < 2)
177  {
178  av_log(NULL, AV_LOG_ERROR, "Incorrect input\n");
179  return 1;
180  }
181 
182  if (video_decode_example(argv[1]) != 0)
183  return 1;
184 
185  return 0;
186 }
av_packet_unref
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:404
AVCodec
AVCodec.
Definition: codec.h:197
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
AVCodecParameters
This struct describes the properties of an encoded stream.
Definition: codec_par.h:52
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:55
av_frame_free
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:112
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:303
AVFormatContext::streams
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1175
AVFrame::pts
int64_t pts
Presentation timestamp in time_base units (time when frame should be shown to user).
Definition: frame.h:396
AVFrame::pkt_duration
int64_t pkt_duration
duration of the corresponding packet, expressed in AVStream->time_base units, 0 if unknown.
Definition: frame.h:565
av_read_frame
int av_read_frame(AVFormatContext *s, AVPacket *pkt)
Return the next frame of a stream.
Definition: utils.c:1668
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:70
AVFrame::data
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:317
av_malloc
#define av_malloc(s)
Definition: tableprint_vlc.h:31
av_find_best_stream
int av_find_best_stream(AVFormatContext *ic, enum AVMediaType type, int wanted_stream_nb, int related_stream, const AVCodec **decoder_ret, int flags)
Find the "best" stream in the file.
Definition: utils.c:4120
avformat_close_input
void avformat_close_input(AVFormatContext **s)
Close an opened input AVFormatContext.
Definition: utils.c:4346
finish
static void finish(void)
Definition: movenc.c:342
AVRational::num
int num
Numerator.
Definition: rational.h:59
av_frame_alloc
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:99
video_decode_example
static int video_decode_example(const char *input_filename)
H264 codec test.
Definition: api-h264-test.c:33
pkt
AVPacket * pkt
Definition: movenc.c:59
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
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: utils.c:482
avcodec_alloc_context3
AVCodecContext * avcodec_alloc_context3(const AVCodec *codec)
Allocate an AVCodecContext and set its fields to default values.
Definition: options.c:141
avcodec_receive_frame
int avcodec_receive_frame(AVCodecContext *avctx, AVFrame *frame)
Return decoded output data from a decoder.
Definition: decode.c:639
ctx
AVFormatContext * ctx
Definition: movenc.c:48
AVFormatContext
Format I/O context.
Definition: avformat.h:1107
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:994
result
and forward the result(frame or status change) to the corresponding input. If nothing is possible
AVStream::time_base
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented.
Definition: avformat.h:870
NULL
#define NULL
Definition: coverity.c:32
fmt_ctx
static AVFormatContext * fmt_ctx
Definition: demuxing_decoding.c:38
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:156
main
int main(int argc, char **argv)
Definition: api-h264-test.c:174
adler32.h
AVFrame::pkt_dts
int64_t pkt_dts
DTS copied from the AVPacket that triggered returning this frame.
Definition: frame.h:403
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:137
av_adler32_update
AVAdler av_adler32_update(AVAdler adler, const uint8_t *buf, size_t len)
Calculate the Adler32 checksum of a buffer.
Definition: adler32.c:44
avcodec_find_decoder
const AVCodec * avcodec_find_decoder(enum AVCodecID id)
Find a registered decoder with a matching codec ID.
Definition: allcodecs.c:915
avformat_find_stream_info
int avformat_find_stream_info(AVFormatContext *ic, AVDictionary **options)
Read packets of a media file to get stream information.
Definition: utils.c:3546
AV_NOPTS_VALUE
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248
printf
printf("static const uint8_t my_array[100] = {\n")
AVPacket::dts
int64_t dts
Decompression timestamp in AVStream->time_base units; the time at which the packet is decompressed.
Definition: packet.h:372
av_image_get_buffer_size
int av_image_get_buffer_size(enum AVPixelFormat pix_fmt, int width, int height, int align)
Return the size in bytes of the amount of data required to store an image with the given parameters.
Definition: imgutils.c:466
av_packet_alloc
AVPacket * av_packet_alloc(void)
Allocate an AVPacket and set its fields to default values.
Definition: avpacket.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:576
i
int i
Definition: input.c:406
AVPacket::pts
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: packet.h:366
avcodec_parameters_to_context
int avcodec_parameters_to_context(AVCodecContext *codec, const AVCodecParameters *par)
Fill the codec context based on the values from the supplied codec parameters.
Definition: codec_par.c:147
av_frame_unref
void av_frame_unref(AVFrame *frame)
Unreference all the buffers referenced by frame and reset the frame fields.
Definition: frame.c:437
avcodec.h
video_stream
static AVStream * video_stream
Definition: demuxing_decoding.c:42
avformat.h
AVCodecContext
main external API structure.
Definition: avcodec.h:379
AVRational::den
int den
Denominator.
Definition: rational.h:60
AVPacket::stream_index
int stream_index
Definition: packet.h:375
input_filename
static const char * input_filename
Definition: ffplay.c:310
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
av_image_copy_to_buffer
int av_image_copy_to_buffer(uint8_t *dst, int dst_size, const uint8_t *const src_data[4], const int src_linesize[4], enum AVPixelFormat pix_fmt, int width, int height, int align)
Copy image data from an image into a buffer.
Definition: imgutils.c:501
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
AVPacket
This structure stores compressed data.
Definition: packet.h:350
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:35
imgutils.h
timestamp.h
AVFrame::linesize
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:334
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
av_ts2str
#define av_ts2str(ts)
Convenience macro, the return value should be used only directly in function arguments but never stan...
Definition: timestamp.h:54