hacks/ffmpeg/test.cc

   1 #include <iostream>
   2 extern "C" {
   3 #include <libavcodec/avcodec.h>
   4 #include <libavformat/avformat.h>
   5 #include <libswscale/swscale.h>
   6 }
   7
   8 using namespace std;
   9
  10 char const video[] = "./starwars.mpg";//Ghostbusters.avi";
  11
  12 static void
  13 save_frame (AVFrame *frame, int width, int height, int N)
  14 {
  15         char filename[32];
  16
  17         sprintf (filename, "frame%d.ppm", N);
  18         FILE* file = fopen (filename, "wb");
  19         if (file == NULL) {
  20                 return;
  21         }
  22
  23         fprintf (file, "P6\n%d %d\n255\n", width, height);
  24
  25         for (int y = 0; y < height; y++) {
  26                 fwrite (frame->data[0] + y * frame->linesize[0], 1, width * 3, file);
  27         }
  28
  29         fclose (file);
  30 }
  31
  32 int
  33 main (int argc, char* argv[])
  34 {
  35         av_register_all ();
  36
  37         AVFormatContext* format_context = NULL;
  38         if (avformat_open_input (&format_context, video, NULL, NULL) != 0) {
  39                 fprintf (stderr, "avformat_open_input failed.\n");
  40                 return -1;
  41         }
  42
  43         if (avformat_find_stream_info (format_context, NULL) < 0) {
  44                 fprintf (stderr, "av_find_stream_info failed.\n");
  45                 return -1;
  46         }
  47
  48         av_dump_format (format_context, 0, video, 0);
  49
  50         int video_stream = -1;
  51         for (uint32_t i = 0; i < format_context->nb_streams; ++i) {
  52                 if (format_context->streams[i]->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
  53                         video_stream = i;
  54                         break;
  55                 }
  56         }
  57
  58         AVCodecContext* decoder_context = format_context->streams[video_stream]->codec;
  59
  60         AVCodec* decoder = avcodec_find_decoder (decoder_context->codec_id);
  61         if (decoder == NULL) {
  62                 fprintf (stderr, "avcodec_find_decoder failed.\n");
  63                 return -1;
  64         }
  65
  66         if (avcodec_open2 (decoder_context, decoder, NULL) < 0) {
  67                 fprintf (stderr, "avcodec_open failed.\n");
  68                 return -1;
  69         }
  70
  71         /* XXX */
  72         if (decoder_context->time_base.num > 1000 && decoder_context->time_base.den == 1) {
  73                 decoder_context->time_base.den = 1000;
  74         }
  75
  76         AVCodec* encoder = avcodec_find_encoder (CODEC_ID_JPEG2000);
  77         if (encoder == NULL) {
  78                 cerr << "avcodec_find_encoder failed.\n";
  79                 return -1;
  80         }
  81
  82         AVCodecContext* encoder_context = avcodec_alloc_context3 (encoder);
  83
  84         cout << decoder_context->width << " x " << decoder_context->height << "\n";
  85         encoder_context->width = decoder_context->width;
  86         encoder_context->height = decoder_context->height;
  87         /* XXX */
  88         encoder_context->time_base = (AVRational) {1, 25};
  89         encoder_context->pix_fmt = PIX_FMT_YUV420P;
  90         encoder_context->compression_level = 0;
  91
  92         if (avcodec_open2 (encoder_context, encoder, NULL) < 0) {
  93                 cerr << "avcodec_open failed.\n";
  94                 return -1;
  95         }
  96
  97         AVFrame* frame = avcodec_alloc_frame ();
  98
  99         AVFrame* frame_RGB = avcodec_alloc_frame ();
 100         if (frame_RGB == NULL) {
 101                 fprintf (stderr, "avcodec_alloc_frame failed.\n");
 102                 return -1;
 103         }
 104
 105         FILE* outfile = fopen ("output", "wb");
 106
 107         int num_bytes = avpicture_get_size (PIX_FMT_RGB24, decoder_context->width, decoder_context->height);
 108         uint8_t* buffer = (uint8_t *) malloc (num_bytes);
 109
 110         avpicture_fill ((AVPicture *) frame_RGB, buffer, PIX_FMT_RGB24, decoder_context->width, decoder_context->height);
 111
 112         /* alloc image and output buffer */
 113         int outbuf_size = 100000;
 114         uint8_t* outbuf = (uint8_t *) malloc (outbuf_size);
 115         int out_size = 0;
 116
 117         AVPacket packet;
 118         int i = 0;
 119         while (av_read_frame (format_context, &packet) >= 0) {
 120
 121                 int frame_finished;
 122
 123                 if (packet.stream_index == video_stream) {
 124                         avcodec_decode_video2 (decoder_context, frame, &frame_finished, &packet);
 125
 126                         if (frame_finished) {
 127                                 static struct SwsContext *img_convert_context;
 128
 129                                 if (img_convert_context == NULL) {
 130                                         int w = decoder_context->width;
 131                                         int h = decoder_context->height;
 132
 133                                         img_convert_context = sws_getContext (
 134                                                 w, h,
 135                                                 decoder_context->pix_fmt,
 136                                                 w, h, PIX_FMT_RGB24, SWS_BICUBIC,
 137                                                 NULL, NULL, NULL
 138                                                 );
 139
 140                                         if (img_convert_context == NULL) {
 141                                                 fprintf (stderr, "sws_getContext failed.\n");
 142                                                 return -1;
 143                                         }
 144                                 }
 145
 146                                 sws_scale (
 147                                         img_convert_context, frame->data, frame->linesize, 0,
 148                                         decoder_context->height, frame_RGB->data, frame_RGB->linesize
 149                                         );
 150
 151                                 out_size = avcodec_encode_video (encoder_context, outbuf, outbuf_size, frame);
 152                                 ++i;
 153                                 if (i == 200) {
 154                                         fwrite (outbuf, 1, out_size, outfile);
 155                                 }
 156                         }
 157                 }
 158
 159                 av_free_packet (&packet);
 160         }
 161
 162         while (out_size) {
 163                 out_size = avcodec_encode_video (encoder_context, outbuf, outbuf_size, NULL);
 164                 fwrite (outbuf, 1, out_size, outfile);
 165         }
 166
 167         fclose (outfile);
 168         free (buffer);
 169         av_free (frame_RGB);
 170         av_free (frame);
 171         avcodec_close (decoder_context);
 172         avcodec_close (encoder_context);
 173         avformat_close_input (&format_context);
 174
 175         return 0;
 176 }