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lavfutils.c
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1 /*
2  * Copyright 2012 Stefano Sabatini <stefasab gmail com>
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #include "libavutil/imgutils.h"
22 #include "lavfutils.h"
23 
24 int ff_load_image(uint8_t *data[4], int linesize[4],
25  int *w, int *h, enum AVPixelFormat *pix_fmt,
26  const char *filename, void *log_ctx)
27 {
29  AVFormatContext *format_ctx = NULL;
30  AVCodec *codec;
31  AVCodecContext *codec_ctx;
32  AVFrame *frame;
33  int frame_decoded, ret = 0;
34  AVPacket pkt;
35  AVDictionary *opt=NULL;
36 
37  av_init_packet(&pkt);
38 
40 
41  iformat = av_find_input_format("image2");
42  if ((ret = avformat_open_input(&format_ctx, filename, iformat, NULL)) < 0) {
43  av_log(log_ctx, AV_LOG_ERROR,
44  "Failed to open input file '%s'\n", filename);
45  return ret;
46  }
47 
48  if ((ret = avformat_find_stream_info(format_ctx, NULL)) < 0) {
49  av_log(log_ctx, AV_LOG_ERROR, "Find stream info failed\n");
50  return ret;
51  }
52 
53  codec_ctx = format_ctx->streams[0]->codec;
54  codec = avcodec_find_decoder(codec_ctx->codec_id);
55  if (!codec) {
56  av_log(log_ctx, AV_LOG_ERROR, "Failed to find codec\n");
57  ret = AVERROR(EINVAL);
58  goto end;
59  }
60 
61  av_dict_set(&opt, "thread_type", "slice", 0);
62  if ((ret = avcodec_open2(codec_ctx, codec, &opt)) < 0) {
63  av_log(log_ctx, AV_LOG_ERROR, "Failed to open codec\n");
64  goto end;
65  }
66 
67  if (!(frame = av_frame_alloc()) ) {
68  av_log(log_ctx, AV_LOG_ERROR, "Failed to alloc frame\n");
69  ret = AVERROR(ENOMEM);
70  goto end;
71  }
72 
73  ret = av_read_frame(format_ctx, &pkt);
74  if (ret < 0) {
75  av_log(log_ctx, AV_LOG_ERROR, "Failed to read frame from file\n");
76  goto end;
77  }
78 
79  ret = avcodec_decode_video2(codec_ctx, frame, &frame_decoded, &pkt);
80  if (ret < 0 || !frame_decoded) {
81  av_log(log_ctx, AV_LOG_ERROR, "Failed to decode image from file\n");
82  if (ret >= 0)
83  ret = -1;
84  goto end;
85  }
86 
87  *w = frame->width;
88  *h = frame->height;
89  *pix_fmt = frame->format;
90 
91  if ((ret = av_image_alloc(data, linesize, *w, *h, *pix_fmt, 16)) < 0)
92  goto end;
93  ret = 0;
94 
95  av_image_copy(data, linesize, (const uint8_t **)frame->data, frame->linesize, *pix_fmt, *w, *h);
96 
97 end:
98  av_packet_unref(&pkt);
99  avcodec_close(codec_ctx);
100  avformat_close_input(&format_ctx);
101  av_frame_free(&frame);
102  av_dict_free(&opt);
103 
104  if (ret < 0)
105  av_log(log_ctx, AV_LOG_ERROR, "Error loading image file '%s'\n", filename);
106  return ret;
107 }
#define NULL
Definition: coverity.c:32
static enum AVPixelFormat pix_fmt
This structure describes decoded (raw) audio or video data.
Definition: frame.h:181
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:101
misc image utilities
int av_image_alloc(uint8_t *pointers[4], int linesizes[4], int w, int h, enum AVPixelFormat pix_fmt, int align)
Allocate an image with size w and h and pixel format pix_fmt, and fill pointers and linesizes accordi...
Definition: imgutils.c:191
static AVPacket pkt
AVCodec.
Definition: avcodec.h:3392
Format I/O context.
Definition: avformat.h:1314
uint8_t
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:141
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:90
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1382
static AVFrame * frame
#define av_log(a,...)
int avcodec_close(AVCodecContext *avctx)
Close a given AVCodecContext and free all the data associated with it (but not the AVCodecContext its...
Definition: utils.c:2529
int width
width and height of the video frame
Definition: frame.h:230
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
int avcodec_decode_video2(AVCodecContext *avctx, AVFrame *picture, int *got_picture_ptr, const AVPacket *avpkt)
Decode the video frame of size avpkt->size from avpkt->data into picture.
Definition: utils.c:2091
#define AVERROR(e)
Definition: error.h:43
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:154
void av_dict_free(AVDictionary **pm)
Free all the memory allocated for an AVDictionary struct and all keys and values. ...
Definition: dict.c:199
void av_image_copy(uint8_t *dst_data[4], int dst_linesizes[4], const uint8_t *src_data[4], const int src_linesizes[4], enum AVPixelFormat pix_fmt, int width, int height)
Copy image in src_data to dst_data.
Definition: imgutils.c:302
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:896
AVInputFormat * av_find_input_format(const char *short_name)
Find AVInputFormat based on the short name of the input format.
Definition: format.c:160
int ff_load_image(uint8_t *data[4], int linesize[4], int *w, int *h, enum AVPixelFormat *pix_fmt, const char *filename, void *log_ctx)
Load image from filename and put the resulting image in data.
Definition: lavfutils.c:24
int format
format of the frame, -1 if unknown or unset Values correspond to enum AVPixelFormat for video frames...
Definition: frame.h:242
static AVInputFormat * iformat
Definition: ffprobe.c:217
enum AVCodecID codec_id
Definition: avcodec.h:1549
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:209
main external API structure.
Definition: avcodec.h:1532
AVCodec * avcodec_find_decoder(enum AVCodecID id)
Find a registered decoder with a matching codec ID.
Definition: utils.c:2629
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:545
int av_dict_set(AVDictionary **pm, const char *key, const char *value, int flags)
Set the given entry in *pm, overwriting an existing entry.
Definition: dict.c:69
int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options)
Initialize the AVCodecContext to use the given AVCodec.
Definition: utils.c:1170
int av_read_frame(AVFormatContext *s, AVPacket *pkt)
Return the next frame of a stream.
Definition: utils.c:1509
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:192
int avformat_find_stream_info(AVFormatContext *ic, AVDictionary **options)
Read packets of a media file to get stream information.
Definition: utils.c:3139
void av_init_packet(AVPacket *pkt)
Initialize optional fields of a packet with default values.
Definition: avpacket.c:33
void avformat_close_input(AVFormatContext **s)
Close an opened input AVFormatContext.
Definition: utils.c:3777
int avformat_open_input(AVFormatContext **ps, const char *url, AVInputFormat *fmt, AVDictionary **options)
Open an input stream and read the header.
Definition: utils.c:422
int height
Definition: frame.h:230
AVPixelFormat
Pixel format.
Definition: pixfmt.h:61
This structure stores compressed data.
Definition: avcodec.h:1444
void av_register_all(void)
Initialize libavformat and register all the muxers, demuxers and protocols.
Definition: allformats.c:51
Miscellaneous utilities which make use of the libavformat library.