我们必须显式添加音频流。
就像是:ffmpeg.output(overlaid_vid_stream, audio_stream, dest)
.
首先使用 FFmpeg CLI 创建合成输入视频和背景(只是为了使发布的解决方案可重复且“自包含”)。
-
创建带有音频的输入视频:
ffmpeg -y -f lavfi -i testsrc=size=128x72:rate=1 -f lavfi -i sine=frequency=400 -f lavfi -i sine=frequency=1000 -filter_complex "[1:a][2:a]amix=inputs=2" -vcodec libx264 -g 10 -crf 17 -pix_fmt yuv420p -acodec aac -ar 22050 -t 50 in.mp4
-
创建黄色背景图像:
ffmpeg.exe -y -f lavfi -i color=yellow:size=128x72 -frames:v 1 background.png
例如,大小为 128x72(假设您的输入为 1280x720)。
以下代码示例适用trim
, setpts
, crop
and overlay
过滤并添加源音频:
source = 'in.mp4'
background = 'background.png'
dest = 'out.mp4'
end = 40
start = 10
duration = end - start
vid_stream = ffmpeg.input(source).video # Source video stream
audio_stream = ffmpeg.input(source).audio # Source audio stream
vid_background = ffmpeg.input(background).video # Background video stream
trimed_vid_stream = vid_stream.trim(start=start, duration=duration).filter('setpts', 'PTS-STARTPTS').crop(10, 0, 108, 72) # Source video stream after trimming and cropping
overlaid_vid_stream = ffmpeg.overlay(vid_background, trimed_vid_stream, x=0, y=18) # Video stream overlay of background and trimed_vid_stream
trimed_audio_stream = audio_stream.filter('atrim', start=start, duration=duration).filter('asetpts', 'PTS-STARTPTS') # Trimming the audio
output_video_and_audio = ffmpeg.output(overlaid_vid_stream, trimed_audio_stream, dest) # Output - video applies overlaid_vid_stream, and audio applies trimmed source audio
output_video_and_audio.overwrite_output().run() # Execute FFmpeg
我修改了你的命名使其更有意义(命名一切stream
使其难以遵循)。
我还删除了该方法,并将参数设置为特定值(只是为了使发布的解决方案可重现)。
该解决方案应用以下主要阶段:
-
创建对视频和音频流的引用:
vid_stream = ffmpeg.input(source).video # Source video stream
audio_stream = ffmpeg.input(source).audio # Source audio stream
-
定义视频过滤器:
vid_background = ffmpeg.input(background).video # Background video stream
trimed_vid_stream = vid_stream.trim(start=start, duration=duration).filter('setpts', 'PTS-STARTPTS').crop(10, 0, 108, 72) # Source video stream after trimming and cropping
overlaid_vid_stream = ffmpeg.overlay(vid_background, trimed_vid_stream, x=0, y=18) # Video stream overlay of background and trimed_vid_stream
-
定义音频过滤器(修剪音频):
trimed_audio_stream = audio_stream.filter('atrim', start=start, duration=duration).filter('asetpts', 'PTS-STARTPTS') # Trimming the audio
-
定义输出以包括“过滤”视频和修剪后的音频:
output_video_and_audio = ffmpeg.output(overlaid_vid_stream, trimed_audio_stream, dest) # Output - video applies overlaid_vid_stream, and audio applies trimmed source audio
-
执行FFmpeg:
output_video_and_audio.overwrite_output().run() # Execute FFmpeg
Sample output frame:
视频中包含蜂鸣声...