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
33static int video_decode_example(const char *input_filename)
34{
35    const AVCodec *codec = NULL;
36    AVCodecContext *ctx= NULL;
37    AVCodecParameters *origin_par = NULL;
38    AVFrame *fr = NULL;
39    uint8_t *byte_buffer = NULL;
40    AVPacket *pkt;
41    AVFormatContext *fmt_ctx = NULL;
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%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
165finish:
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
174int 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}
187