FFmpeg
api-h264-test.c
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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  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 
48  result = avformat_open_input(&fmt_ctx, input_filename, NULL, NULL);
49  if (result < 0) {
50  av_log(NULL, AV_LOG_ERROR, "Can't open file\n");
51  return result;
52  }
53 
54  result = avformat_find_stream_info(fmt_ctx, NULL);
55  if (result < 0) {
56  av_log(NULL, AV_LOG_ERROR, "Can't get stream info\n");
57  return result;
58  }
59 
60  video_stream = av_find_best_stream(fmt_ctx, AVMEDIA_TYPE_VIDEO, -1, -1, NULL, 0);
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 
80  result = avcodec_parameters_to_context(ctx, origin_par);
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 
111  printf("#tb %d: %d/%d\n", video_stream, fmt_ctx->streams[video_stream]->time_base.num, fmt_ctx->streams[video_stream]->time_base.den);
112  i = 0;
113 
114  result = 0;
115  while (result >= 0) {
116  result = av_read_frame(fmt_ctx, pkt);
117  if (result >= 0 && pkt->stream_index != video_stream) {
118  av_packet_unref(pkt);
119  continue;
120  }
121 
122  if (result < 0)
123  result = avcodec_send_packet(ctx, NULL);
124  else {
125  if (pkt->pts == AV_NOPTS_VALUE)
126  pkt->pts = pkt->dts = i;
127  result = avcodec_send_packet(ctx, pkt);
128  }
129  av_packet_unref(pkt);
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) {
137  result = avcodec_receive_frame(ctx, fr);
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%08lx\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:
166  av_packet_free(&pkt);
167  av_frame_free(&fr);
168  avformat_close_input(&fmt_ctx);
169  avcodec_free_context(&ctx);
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 }
#define NULL
Definition: coverity.c:32
This structure describes decoded (raw) audio or video data.
Definition: frame.h:314
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:505
misc image utilities
static AVFormatContext * fmt_ctx
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
int num
Numerator.
Definition: rational.h:59
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:741
static AVStream * video_stream
int avformat_open_input(AVFormatContext **ps, const char *url, ff_const59 AVInputFormat *fmt, AVDictionary **options)
Open an input stream and read the header.
Definition: utils.c:506
static AVPacket pkt
AVCodec.
Definition: codec.h:190
This struct describes the properties of an encoded stream.
Definition: codec_par.h:52
Format I/O context.
Definition: avformat.h:1243
void av_packet_free(AVPacket **pkt)
Free the packet, if the packet is reference counted, it will be unreferenced first.
Definition: avpacket.c:64
uint8_t
#define av_malloc(s)
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:190
timestamp utils, mostly useful for debugging/logging purposes
unsigned long av_adler32_update(unsigned long adler, const uint8_t *buf, unsigned int len)
Calculate the Adler32 checksum of a buffer.
Definition: adler32.c:44
int64_t pts
Presentation timestamp in time_base units (time when frame should be shown to user).
Definition: frame.h:407
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1311
int avcodec_parameters_to_context(AVCodecContext *codec, const AVCodecParameters *par)
Fill the codec context based on the values from the supplied codec parameters.
Definition: utils.c:2197
static void finish(void)
Definition: movenc.c:345
#define AVERROR_EOF
End of file.
Definition: error.h:55
int main(int argc, char **argv)
#define av_log(a,...)
int av_find_best_stream(AVFormatContext *ic, enum AVMediaType type, int wanted_stream_nb, int related_stream, AVCodec **decoder_ret, int flags)
Find the "best" stream in the file.
Definition: utils.c:4212
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
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:194
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:203
int avcodec_receive_frame(AVCodecContext *avctx, AVFrame *frame)
Return decoded output data from a decoder.
Definition: decode.c:643
static int video_decode_example(const char *input_filename)
H264 codec test.
Definition: api-h264-test.c:33
AVCodecContext * avcodec_alloc_context3(const AVCodec *codec)
Allocate an AVCodecContext and set its fields to default values.
Definition: options.c:172
int width
picture width / height.
Definition: avcodec.h:704
AVFormatContext * ctx
Definition: movenc.c:48
static const char * input_filename
Definition: ffplay.c:312
Public header for Adler-32 hash function implementation.
int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt)
Supply raw packet data as input to a decoder.
Definition: decode.c:580
Libavcodec external API header.
int64_t pkt_duration
duration of the corresponding packet, expressed in AVStream->time_base units, 0 if unknown...
Definition: frame.h:593
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:187
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:345
main external API structure.
Definition: avcodec.h:531
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:606
int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options)
Initialize the AVCodecContext to use the given AVCodec.
Definition: utils.c:544
int av_read_frame(AVFormatContext *s, AVPacket *pkt)
Return the next frame of a stream.
Definition: utils.c:1727
AVCodec * avcodec_find_decoder(enum AVCodecID id)
Find a registered decoder with a matching codec ID.
Definition: allcodecs.c:945
void av_frame_unref(AVFrame *frame)
Unreference all the buffers referenced by frame and reset the frame fields.
Definition: frame.c:553
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:328
int64_t pkt_dts
DTS copied from the AVPacket that triggered returning this frame.
Definition: frame.h:423
Main libavformat public API header.
int avformat_find_stream_info(AVFormatContext *ic, AVDictionary **options)
Read packets of a media file to get stream information.
Definition: utils.c:3586
int den
Denominator.
Definition: rational.h:60
void avformat_close_input(AVFormatContext **s)
Close an opened input AVFormatContext.
Definition: utils.c:4461
#define av_ts2str(ts)
Convenience macro, the return value should be used only directly in function arguments but never stan...
Definition: timestamp.h:54
printf("static const uint8_t my_array[100] = {\n")
AVPacket * av_packet_alloc(void)
Allocate an AVPacket and set its fields to default values.
Definition: avpacket.c:53
int64_t dts
Decompression timestamp in AVStream->time_base units; the time at which the packet is decompressed...
Definition: packet.h:362
and forward the result(frame or status change) to the corresponding input.If nothing is possible
#define av_freep(p)
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1049
int stream_index
Definition: packet.h:365
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented...
Definition: avformat.h:913
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
This structure stores compressed data.
Definition: packet.h:340
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: packet.h:356
int i
Definition: input.c:407
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248