ffmpeg调整缩放裁剪视频的基础知识 1. resize and scale video 调整视频的大小和尺寸 1-1.调整视频大小(resize)是改变视频的宽度和高度。 使用-s参数实现,语法:ffmpeg -i input_file -s wxh output_file (wxh是宽x高,比如320x240) 调整视频的尺寸(scale)是改变帧的数量。 1-2.预定义的视频大小简写如下: 2...
注意:-r参数 设置的是 输出视频的帧率 , 输入视频的帧率是固定的 , 如果 输入视频的帧率 与该-r参数 设置的 输出视频帧率不同 , 如果 输入视频帧率 > 输出视频帧率 : 通过 丢弃视频帧 来调整输出视频的帧率。 如果 输入视频帧率 < 输出视频帧率 : 通过 增加重复帧 来调整输出视频的帧率。 2、设置输出视频...
在继续播放之前,先将暂停期间流逝的时间加到frame_timer中 is->frame_timer += av_gettime_relative() / 1000000.0 - is->video_clk.last_updated; set_clock(&is->video_clk, get_clock(&is->video_clk), is->video_clk.serial); } is->paused = is->audio_clk.paused = is->video_clk.paused ...
ffmpeg -i in.mp4 -vf scale=iw0.6:ih0.6 out.mp4 ffmpeg -i in.mp4 -vf scale=200:200/a out.mp4 视频裁剪 Crop 视频裁剪指的是从指定视频的某个区域(通常是矩形)取出部分画面。 crop video filter crop filter的语法如下: crop=ow[:oh[❌[y:[:keep_aspect]]] 除了能使用scale filter提供的参数...
Which one is faster, more performant for things like frigate? If I want to downscale a 4k video to 1080p. In terms of decoding, the two speeds are about the same. In terms of encoding, this is twice as fast as before and can achieve more complex filter combinations. ...
2. Downscale the video resolution. 3. Lower the video bitrate. 4. Decrease the frame rate. 5. Remove unwanted portions of the video. According to your specific needs, select the appropriate compression method and execute the corresponding FFmpeg command to compress the video. 🧐 About the te...
ffmpeg -i video.mp4 -vf "fps=10,scale=320:-1:flags=lanczos" -c:v gif -f gif out.gif 1.音频PCM/AAC文件提取 音频数据提取是一个涉及到音频编解码、解复用以及可能的格式转换的复杂过程。从音频文件中提取PCM(脉冲编码调制,一种未压缩的音频数据格式)和AAC(高级音频编码,一种有损压缩的音频编码标准...
(kind == Images.Thumbnails.MINI_KIND) {// Scale down the bitmap if it's too large.intwidth = bitmap.getWidth();intheight = bitmap.getHeight();intmax = Math.max(width, height);if(max >512) {floatscale =512f/ max;intw = Math.round(scale * width);inth = Math.round(scale *...
multiVideo多画面拼接reverseVideo反向播放 videoDoubleDown视频缩小一倍videoDouble视频放大一倍 videoSpeed2倍速播放denoiseVideo视频降噪 audioFadeIn音频淡入audioFadeOut音频淡出 videoBright修改视频亮度videoContrast修改视频对比度 picInPicVideo画中画videoScale视频固定缩放 ...
Digital Image Processing 4 - Grayscale image II (image data type and bit-plane) Digital Image Processing 5 - Histogram equalization Digital Image Processing 6 - Image Filter (Low pass filters) Video Processing 1 - Object detection (tagging cars) by thresholding color ...