+++ /dev/null
-#include <libavcodec/avcodec.h>
-#include <libavformat/avformat.h>
-#include <libswscale/swscale.h>
-
-char const video[] = "/home/carl/Films/A town called panic.divx";//Ghostbusters.avi";
-
-static void
-save_frame (AVFrame *frame, int width, int height, int N)
-{
- char filename[32];
-
- sprintf (filename, "frame%d.ppm", N);
- FILE* file = fopen (filename, "wb");
- if (file == NULL) {
- return;
- }
-
- fprintf (file, "P6\n%d %d\n255\n", width, height);
-
- for (int y = 0; y < height; y++) {
- fwrite (frame->data[0] + y * frame->linesize[0], 1, width * 3, file);
- }
-
- fclose (file);
-}
-
-int
-main (int argc, char* argv[])
-{
- av_register_all ();
-
- AVFormatContext* format_context = NULL;
- if (avformat_open_input (&format_context, video, NULL, NULL) != 0) {
- fprintf (stderr, "avformat_open_input failed.\n");
- return -1;
- }
-
- if (avformat_find_stream_info (format_context, NULL) < 0) {
- fprintf (stderr, "av_find_stream_info failed.\n");
- return -1;
- }
-
- av_dump_format (format_context, 0, video, 0);
-
- int video_stream = -1;
- for (uint32_t i = 0; i < format_context->nb_streams; ++i) {
- if (format_context->streams[i]->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
- video_stream = i;
- break;
- }
- }
-
- AVCodecContext* codec_context = format_context->streams[video_stream]->codec;
-
- AVCodec* codec = avcodec_find_decoder (codec_context->codec_id);
- if (codec == NULL) {
- fprintf (stderr, "avcodec_find_decoder failed.\n");
- return -1;
- }
-
- if (avcodec_open2 (codec_context, codec, NULL) < 0) {
- fprintf (stderr, "avcodec_open failed.\n");
- return -1;
- }
-
- if (codec_context->time_base.num > 1000 && codec_context->time_base.den == 1) {
- codec_context->time_base.den = 1000;
- }
-
- AVFrame* frame = avcodec_alloc_frame ();
-
- AVFrame* frame_RGB = avcodec_alloc_frame ();
- if (frame_RGB == NULL) {
- fprintf (stderr, "avcodec_alloc_frame failed.\n");
- return -1;
- }
-
- int num_bytes = avpicture_get_size (PIX_FMT_RGB24, codec_context->width, codec_context->height);
- uint8_t* buffer = (uint8_t *) malloc (num_bytes);
-
- avpicture_fill ((AVPicture *) frame_RGB, buffer, PIX_FMT_RGB24, codec_context->width, codec_context->height);
-
- int i = 0;
- AVPacket packet;
- while (av_read_frame (format_context, &packet) >= 0) {
-
- int frame_finished;
-
- if (packet.stream_index == video_stream) {
- avcodec_decode_video2 (codec_context, frame, &frame_finished, &packet);
-
- if (frame_finished) {
- static struct SwsContext *img_convert_context;
-
- if (img_convert_context == NULL) {
- int w = codec_context->width;
- int h = codec_context->height;
-
- img_convert_context = sws_getContext (
- w, h,
- codec_context->pix_fmt,
- w, h, PIX_FMT_RGB24, SWS_BICUBIC,
- NULL, NULL, NULL
- );
-
- if (img_convert_context == NULL) {
- fprintf (stderr, "sws_getContext failed.\n");
- return -1;
- }
- }
-
- sws_scale (
- img_convert_context, frame->data, frame->linesize, 0,
- codec_context->height, frame_RGB->data, frame_RGB->linesize
- );
-
- ++i;
- if (i > 100 && i < 150) {
- save_frame (frame_RGB, codec_context->width, codec_context->height, i);
- }
- }
- }
-
- av_free_packet (&packet);
- }
-
- free (buffer);
- av_free (frame_RGB);
- av_free (frame);
- avcodec_close(codec_context);
- avformat_close_input (&format_context);
-
- return 0;
-}