命令行采集

ffmpeg在windows下查看设备的命令：

  1. ffmpeg -list_devices true -f dshow -i dummy

ffmpeg在windows下查看摄像机支持的编码参数

  1. ffmpeg -list_options true -f dshow -i video="Integrated Webcam"
  1. ffmpeg -f dshow -i video="Integrated Webcam" -vcodec libx264 out.mkv
  2. ffmpeg -f dshow -i video="Integrated Webcam" -r 5 -vcodec libx264 -preset:v ultrafast -tune:v zerolatency out1.mp4
  3. ffmpeg -f dshow -i video="Integrated Webcam" -vcodec libx264 mycamera.h264

ffplay 播放摄像头采集的视频

  1. //播放yuv数据
  2. ffplay -i F:\virtual-code\yuv_encode.c\video.yuv -pix_fmt yuv420p  -s 640x480
  3. //播放y
  4. ffplay -i F:\virtual-code\yuv_encode.c\video.yuv -pix_fmt yuv420p  -s 640x480 -vf extractplanes='y'
  5. //播放u
  6. ffplay -i F:\virtual-code\yuv_encode.c\video.yuv -pix_fmt yuv420p  -s 640x480 -vf extractplanes='u'
  7. //播放v
  8. ffplay -i F:\virtual-code\yuv_encode.c\video.yuv -pix_fmt yuv420p  -s 640x480 -vf extractplanes='v'

调用ffmpeg接口采集

  2. #include <iostream>
  3. #include <strsafe.h>
  5. #define __STDC_CONSTANT_MACROS
  7. extern "C"
  8. {
  9. #include "libavutil/avutil.h"
  10. #include "libavdevice/avdevice.h"
  11. #include "libswscale/swscale.h"
  12. #include "libswresample/swresample.h"
  13. #include "libavutil\samplefmt.h"
  14. #include <stdio.h>
  15. }
  17. #ifdef _MSC_VER
  18. #include <tchar.h>
  19. #include <dshow.h>
  20. #include <atlcomcli.h>
  21. #pragma comment(lib, "Strmiids.lib")
  22. #endif
  24. using namespace std;
  26. int main()
  27. {
  28.     int ret = 0;
  30.     AVFormatContext* fmt_ctx = NULL;
  31.     AVDictionary* options = NULL;
  33.     char errors[1024] = { 0 };
  34.     char device_name[256] = "video=Integrated Webcam";
  35.     char file_name[256] = "collection.yuv";
  36.     char name[128] = { 0 };
  37.     char name_utf8[128] = { 0 };
  39.     av_register_all();
  40.     avdevice_register_all();
  42.     AVInputFormat* in_format = av_find_input_format("dshow");
  43.     if (in_format == NULL)
  44.     {
  45.         printf("av_find_input_format error\n");
  46.     }
  48.     //640*480  30 也可以采集 
  49.     av_dict_set(&options, "video_size", "1280*720", 0);
  50.     av_dict_set(&options, "framerate", "10", 0);
  51.     av_dict_set(&options, "pixel_format", "yuyv422", 0);
  53.     if ((ret = avformat_open_input(&fmt_ctx, device_name, in_format, &options)) != 0)
  54.     {
  55.         av_strerror(ret, errors, 1024);
  56.         printf("Failed to open video device, [%s][%d]\n", errors, ret);
  57.         return -1;
  58.     }
  61.     AVPacket* pkt = av_packet_alloc();
  62.     av_init_packet(pkt);
  63.     FILE* out_file = fopen(file_name, "wb+");
  65.     av_dump_format(fmt_ctx, 0, device_name, 0);
  67.     while (!av_read_frame(fmt_ctx, pkt))
  68.     {
  69.         printf("Size of collected data %d\n", pkt->size);
  71.         //640 * 480 * 2
  72.         // (宽*高)*（yuv420=1.5/yuv422=2/yuv444=3）
  73.         fwrite(pkt->data, 1, 1280 * 720 *2, out_file);
  74.         fflush(out_file);
  75.         av_packet_unref(pkt);
  76.     }
  78.     av_packet_free(&pkt);
  79.     avformat_close_input(&fmt_ctx);
  80.     fclose(out_file);
  82.     // ffplay -video_size 640*480 -pixel_format yuyv422 -framerate 30 collection.yuv
  83.     return 0;
  84. }

注：调用接口采集时发现，每个采集的分辨率都对应一套自己的参数
video_size —-> 640*480
framerate ——> 30
pixel_format ——> 摄像头自身决定，不能更改