我正在使用ffmpeg 覆盖过滤器向视频添加水印,并且我想保留视频的原始质量。这是ffmpeg -i
原始视频的输出:
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'original_recording.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2mp41
encoder : Lavf57.25.100
Duration: 00:03:59.13, start: 0.000000, bitrate: 1932 kb/s
Stream #0:0(und): Video: mpeg4 (Simple Profile) (mp4v / 0x7634706D), yuv420p, 1472x828 [SAR 1:1 DAR 16:9], 1796 kb/s, 24.96 fps, 25 tbr, 12800 tbn, 25 tbc (default)
Metadata:
handler_name : VideoHandler
Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 129 kb/s (default)
Metadata:
handler_name : SoundHandler
这是我用来在右下角覆盖图像文件的命令(基本上是水印):
ffmpeg -i original_recording.mp4 -i watermark.png -filter_complex "overlay=W-w-45:H-h-35" -c:v libx264 -strict -2 output.mp4
我添加了 libx264 选项,因为输出非常糟糕。但是,当我使用它时,输出文件的大小比原始文件小得多。(播放视频时没有明显的质量损失,但如果可能的话,我宁愿不损失质量)。我不是视频格式方面的专家,说实话我有点迷茫。
我已经尝试了 -crf 选项,但它给出了这个错误消息:
Codec AVOption crf (Select the quality for constant quality mode) specified for output file #0 (output.mp4) has not been used for any stream. The most likely reason is either wrong type (e.g. a video option with no video streams) or that it is a private option of some encoder which was not actually used for any stream.
将图像叠加为水印同时尽可能保持原始视频质量的最佳方法是什么?