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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 {
28  AVInputFormat *iformat = NULL;
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 
36  av_init_packet(&pkt);
37 
39 
40  iformat = av_find_input_format("image2");
41  if ((ret = avformat_open_input(&format_ctx, filename, iformat, NULL)) < 0) {
42  av_log(log_ctx, AV_LOG_ERROR,
43  "Failed to open input file '%s'\n", filename);
44  return ret;
45  }
46 
47  codec_ctx = format_ctx->streams[0]->codec;
48  codec = avcodec_find_decoder(codec_ctx->codec_id);
49  if (!codec) {
50  av_log(log_ctx, AV_LOG_ERROR, "Failed to find codec\n");
51  ret = AVERROR(EINVAL);
52  goto end;
53  }
54 
55  if ((ret = avcodec_open2(codec_ctx, codec, NULL)) < 0) {
56  av_log(log_ctx, AV_LOG_ERROR, "Failed to open codec\n");
57  goto end;
58  }
59 
60  if (!(frame = av_frame_alloc()) ) {
61  av_log(log_ctx, AV_LOG_ERROR, "Failed to alloc frame\n");
62  ret = AVERROR(ENOMEM);
63  goto end;
64  }
65 
66  ret = av_read_frame(format_ctx, &pkt);
67  if (ret < 0) {
68  av_log(log_ctx, AV_LOG_ERROR, "Failed to read frame from file\n");
69  goto end;
70  }
71 
72  ret = avcodec_decode_video2(codec_ctx, frame, &frame_decoded, &pkt);
73  if (ret < 0 || !frame_decoded) {
74  av_log(log_ctx, AV_LOG_ERROR, "Failed to decode image from file\n");
75  goto end;
76  }
77  ret = 0;
78 
79  *w = frame->width;
80  *h = frame->height;
81  *pix_fmt = frame->format;
82 
83  if ((ret = av_image_alloc(data, linesize, *w, *h, *pix_fmt, 16)) < 0)
84  goto end;
85  ret = 0;
86 
87  av_image_copy(data, linesize, (const uint8_t **)frame->data, frame->linesize, *pix_fmt, *w, *h);
88 
89 end:
90  av_free_packet(&pkt);
91  avcodec_close(codec_ctx);
92  avformat_close_input(&format_ctx);
93  av_freep(&frame);
94 
95  if (ret < 0)
96  av_log(log_ctx, AV_LOG_ERROR, "Error loading image file '%s'\n", filename);
97  return ret;
98 }