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/**
* 最简单的基于FFmpeg的AVFilter例子（叠加水印）
* Simplest FFmpeg AVfilter Example (Watermark)
*
* 雷霄骅 Lei Xiaohua
* [email protected]
* 中国传媒大学/数字电视技术
* Communication University of China / Digital TV Technology
* http://blog.csdn.net/leixiaohua1020
*
* 本程序使用FFmpeg的AVfilter实现了视频的水印叠加功能。
* 可以将一张PNG图片作为水印叠加到视频上。
* 是最简单的FFmpeg的AVFilter方面的教程。
* 适合FFmpeg的初学者。
*
* This software uses FFmpeg‘s AVFilter to add watermark in a video file.
* It can add a PNG format picture as watermark to a video file.
* It‘s the simplest example based on FFmpeg‘s AVFilter.
* Suitable for beginner of FFmpeg
*
*/
#include "stdafx.h"
#define ENABLE_SDL 1
#define ENABLE_YUVFILE 0
extern "C"
{
#include "libavcodec/avcodec.h"
#include "libavformat/avformat.h"
#include "libavfilter/avfiltergraph.h"
#include "libavfilter/avcodec.h"
#include "libavfilter/buffersink.h"
#include "libavfilter/buffersrc.h"
#include "libavutil/avutil.h"
#include "libswscale/swscale.h"
//SDL
#include "sdl/SDL.h"
#include "sdl/SDL_thread.h"
};
const char *filter_descr = "movie=my_logo.png[wm];[in][wm]overlay=5:5[out]";
static AVFormatContext *pFormatCtx;
static AVCodecContext *pCodecCtx;
AVFilterContext *buffersink_ctx;
AVFilterContext *buffersrc_ctx;
AVFilterGraph *filter_graph;
static int video_stream_index = -1;
static int64_t last_pts = AV_NOPTS_VALUE;
static int open_input_file(const char *filename)
{
int ret;
AVCodec *dec;
if ((ret = avformat_open_input(&pFormatCtx, filename, NULL, NULL)) < 0) {
av_log(NULL, AV_LOG_ERROR, "Cannot open input file\n");
return ret;
}
if ((ret = avformat_find_stream_info(pFormatCtx, NULL)) < 0) {
av_log(NULL, AV_LOG_ERROR, "Cannot find stream information\n");
return ret;
}
/* select the video stream */
ret = av_find_best_stream(pFormatCtx, AVMEDIA_TYPE_VIDEO, -1, -1, &dec, 0);
if (ret < 0) {
av_log(NULL, AV_LOG_ERROR, "Cannot find a video stream in the input file\n");
return ret;
}
video_stream_index = ret;
pCodecCtx = pFormatCtx->streams[video_stream_index]->codec;
/* init the video decoder */
if ((ret = avcodec_open2(pCodecCtx, dec, NULL)) < 0) {
av_log(NULL, AV_LOG_ERROR, "Cannot open video decoder\n");
return ret;
}
return 0;
}
static int init_filters(const char *filters_descr)
{
char args[512];
int ret;
AVFilter *buffersrc = avfilter_get_by_name("buffer");
AVFilter *buffersink = avfilter_get_by_name("ffbuffersink");
AVFilterInOut *outputs = avfilter_inout_alloc();
AVFilterInOut *inputs = avfilter_inout_alloc();
enum PixelFormat pix_fmts[] = { PIX_FMT_GRAY8, PIX_FMT_NONE };
AVBufferSinkParams *buffersink_params;
filter_graph = avfilter_graph_alloc();
/* buffer video source: the decoded frames from the decoder will be inserted here. */
_snprintf(args, sizeof(args),
"video_size=%dx%d:pix_fmt=%d:time_base=%d/%d:pixel_aspect=%d/%d",
pCodecCtx->width, pCodecCtx->height, pCodecCtx->pix_fmt,
pCodecCtx->time_base.num, pCodecCtx->time_base.den,
pCodecCtx->sample_aspect_ratio.num, pCodecCtx->sample_aspect_ratio.den);
ret = avfilter_graph_create_filter(&buffersrc_ctx, buffersrc, "in",
args, NULL, filter_graph);
if (ret < 0) {
av_log(NULL, AV_LOG_ERROR, "Cannot create buffer source\n");
return ret;
}
/* buffer video sink: to terminate the filter chain. */
buffersink_params = av_buffersink_params_alloc();
buffersink_params->pixel_fmts = pix_fmts;
ret = avfilter_graph_create_filter(&buffersink_ctx, buffersink, "out",
NULL, buffersink_params, filter_graph);
av_free(buffersink_params);
if (ret < 0) {
av_log(NULL, AV_LOG_ERROR, "Cannot create buffer sink\n");
return ret;
}
/* Endpoints for the filter graph. */
outputs->name = av_strdup("in");
outputs->filter_ctx = buffersrc_ctx;
outputs->pad_idx = 0;
outputs->next = NULL;
inputs->name = av_strdup("out");
inputs->filter_ctx = buffersink_ctx;
inputs->pad_idx = 0;
inputs->next = NULL;
if ((ret = avfilter_graph_parse(filter_graph, filters_descr,
&inputs, &outputs, NULL)) < 0)
return ret;
if ((ret = avfilter_graph_config(filter_graph, NULL)) < 0)
return ret;
return 0;
}
int _tmain(int argc, _TCHAR* argv[])
{
int ret;
AVPacket packet;
AVFrame frame;
int got_frame;
if (argc != 2) {
fprintf(stderr, "Usage: %s file\n", argv[0]);
return -1;
}
avcodec_register_all();
av_register_all();
avfilter_register_all();
if ((ret = open_input_file(argv[1])) < 0)
goto end;
if ((ret = init_filters(filter_descr)) < 0)
goto end;
#if ENABLE_YUVFILE
FILE *fp_yuv=fopen("test.yuv","wb+");
#endif
#if ENABLE_SDL
SDL_Surface *screen;
SDL_Overlay *bmp;
SDL_Rect rect;
if(SDL_Init(SDL_INIT_VIDEO | SDL_INIT_AUDIO | SDL_INIT_TIMER)) {
printf( "Could not initialize SDL - %s\n", SDL_GetError());
return -1;
}
screen = SDL_SetVideoMode(pCodecCtx->width, pCodecCtx->height, 0, 0);
if(!screen) {
printf("SDL: could not set video mode - exiting\n");
return -1;
}
bmp = SDL_CreateYUVOverlay(pCodecCtx->width, pCodecCtx->height,SDL_YV12_OVERLAY, screen);
#endif
/* read all packets */
while (1) {
AVFilterBufferRef *picref;
if ((ret = av_read_frame(pFormatCtx, &packet)) < 0)
break;
if (packet.stream_index == video_stream_index) {
avcodec_get_frame_defaults(&frame);
got_frame = 0;
ret = avcodec_decode_video2(pCodecCtx, &frame, &got_frame, &packet);
if (ret < 0) {
av_log(NULL, AV_LOG_ERROR, "Error decoding video\n");
break;
}
if (got_frame) {
frame.pts = av_frame_get_best_effort_timestamp(&frame);
/* push the decoded frame into the filtergraph */
if (av_buffersrc_add_frame(buffersrc_ctx, &frame) < 0) {
av_log(NULL, AV_LOG_ERROR, "Error while feeding the filtergraph\n");
break;
}
/* pull filtered pictures from the filtergraph */
while (1) {
ret = av_buffersink_get_buffer_ref(buffersink_ctx, &picref, 0);
if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF)
break;
if (ret < 0)
goto end;
if (picref) {
#if ENABLE_YUVFILE
int y_size=picref->video->w*picref->video->h;
fwrite(picref->data[0],1,y_size,fp_yuv);
fwrite(picref->data[1],1,y_size/4,fp_yuv);
fwrite(picref->data[2],1,y_size/4,fp_yuv);
#endif
#if ENABLE_SDL
SDL_LockYUVOverlay(bmp);
bmp->pixels[0]=picref->data[0];
bmp->pixels[2]=picref->data[1];
bmp->pixels[1]=picref->data[2];
bmp->pitches[0]=picref->linesize[0];
bmp->pitches[2]=picref->linesize[1];
bmp->pitches[1]=picref->linesize[2];
SDL_UnlockYUVOverlay(bmp);
rect.x = 0;
rect.y = 0;
rect.w = picref->video->w;
rect.h = picref->video->h;
SDL_DisplayYUVOverlay(bmp, &rect);
//Delay 40ms
SDL_Delay(40);
#endif
avfilter_unref_bufferp(&picref);
}
}
}
}
av_free_packet(&packet);
}
#if ENABLE_YUVFILE
fclose(fp_yuv);
#endif
end:
avfilter_graph_free(&filter_graph);
if (pCodecCtx)
avcodec_close(pCodecCtx);
avformat_close_input(&pFormatCtx);
if (ret < 0 && ret != AVERROR_EOF) {
char buf[1024];
av_strerror(ret, buf, sizeof(buf));
fprintf(stderr, "Error occurred: %s\n", buf);
return -1;
}
return 0;
}
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