ffmpeg编码

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
#include <libavcodec/avcodec.h>
#include <libavformat/avformat.h>
#include <libavutil/opt.h>

static int ptsIndex = 0;

void encode(AVCodecContext *pContext, AVFrame *pFrame, AVPacket *packet, FILE *pOutFile)
{
    int ret = 0;
    if (pFrame)
        pFrame->pts = ptsIndex++;

    ret = avcodec_send_frame(pContext, pFrame);
    if (ret < 0)
    {
        fprintf(stderr, "Error sending the frame to the encoder\n");
        return;
    }

    while (ret >= 0)
    {return
        ret = avcodec_receive_packet(pContext, packet);
        if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF)
            return;
        else if (ret < 0)
        {
            fprintf(stderr, "Error during encoding\n");
            break;
        }

        packet->stream_index = 0;

        fwrite(packet->data, 1, packet->size, pOutFile);

        av_packet_unref(packet);
    }
}

int main(int argc, char *argv[])
{
    const char *filename, *outfilename;

    const AVCodec *pCodec = NULL;
    AVCodecContext *pContext = NULL;

    FILE *pInputFile;
    FILE *pOutFile;

    AVFrame *pFrame = NULL;
    AVPacket *pPacket = NULL;

    int ret = 0;

    filename = "output.yuv";
    outfilename = "enc.h264";
    do
    {
        pCodec = avcodec_find_encoder(AV_CODEC_ID_H264);
        if (!pCodec)
        {
            fprintf(stderr, "Codec not found\n");
            break;
        }

        pContext = avcodec_alloc_context3(pCodec);
        if (!pContext)
        {
            fprintf(stderr, "Could not allocate video codec context\n");
            break;
        }

        pContext->bit_rate = 400000;
        pContext->width = 352;
        pContext->height = 288;

        pContext->framerate = (AVRational){30, 1};
        pContext->time_base = (AVRational){1, 30};

        pContext->gop_size = 12;
        pContext->max_b_frames = 0;
        pContext->pix_fmt = AV_PIX_FMT_YUV420P;

        if (avcodec_open2(pContext, pCodec, NULL) < 0)
        {
            fprintf(stderr, "Could not open codec: %s\n", av_err2str(ret));
            break;
        }

        pInputFile = fopen(filename, "rb");
        if (!pInputFile)
        {
            fprintf(stderr, "Could not open %s\n", filename);
            break;
        }

        pOutFile = fopen(outfilename, "wb");
        if (!pOutFile)
        {
            fprintf(stderr, "Could not open %s\n", outfilename);
            break;
        }

        pPacket = av_packet_alloc();
        if (!pPacket)
        {
            break;
        }

        pFrame = av_frame_alloc();
        if (!pFrame)
        {
            fprintf(stderr, "Could not allocate video frame\n");
            break;
        }

        pFrame->format = pContext->pix_fmt;
        pFrame->height = pContext->height;
        pFrame->width = pContext->width;

        ret = av_frame_get_buffer(pFrame, 1);
        if (ret != 0)
        {
            printf("frame get buffer fail\n");
            break;
        }

        while (!feof(pInputFile))
        {
            fread(pFrame->data[0], 1, pFrame->width * pFrame->height, pInputFile);     // Y数据
            fread(pFrame->data[1], 1, pFrame->width * pFrame->height / 4, pInputFile); // U数据
            fread(pFrame->data[2], 1, pFrame->width * pFrame->height / 4, pInputFile); // V数据

            encode(pContext, pFrame, pPacket, pOutFile);
        }
    } while (0);

    encode(pContext, NULL, pPacket, pOutFile);

    fclose(pInputFile);
    fclose(pOutFile);
    avcodec_free_context(&pContext);
    av_frame_free(&pFrame);
    av_packet_free(&pPacket);

    return 0;
}