原创
看到 https://www.youtube.com/watch?v=zzHeG7l6FT8 《【東方ボーカルMV】東方言えるかな》里有非常多漂亮的角色（我全都要），觉得很适合拿来做壁纸用，但是又有一些没有画面的场景，可以剪掉来提升观感。
成品链接： https://steamcommunity.com/sharedfiles/filedetails/?id=3659280460
在线观看： https://www.bilibili.com/video/BV1HGFLz8E1H
步骤：
- 从youtube上下载视频和音频
- 使用ffmpeg合并视频和音频
- 使用ffmpeg导出所有帧为图片
- 人工过一遍所有图片，把没有人物的场景删掉
- 整理出来筛选后的图片帧序号并使用ffmpeg裁剪视频
从youtube上下载视频和音频
第一步这里使用
https://snapany.com/zh/youtube-1
直接解析youtube地址拿到googlevideo.com域名的链接来下载。
这里下载到的视频和音频是两个独立的文件。
使用ffmpeg合并视频和音频
让AI生成一个ffmpeg命令
1
ffmpeg -i videoplayback.mp4 -i videoplayback.m4a -c copy output.mp4
使用ffmpeg导出所有帧为图片
让AI生成一个ffmpeg命令
1
ffmpeg -i input.mp4 frame_%05d.png
这里我导出了之后复制一份，一份是原始的，一份用来人工筛选后删除不需要的，方便后续剪视频。
让AI整理出来筛选后的图片帧序号并使用ffmpeg裁剪视频
直接让AI写个python脚本
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
import os
import re
import subprocess
def find_deleted_ranges(images_dir, images2_dir):
all_frames = []
for f in os.listdir(images2_dir):
m = re.match(r"frame_(\d+)\.png", f)
if m:
all_frames.append(int(m.group(1)))
all_frames.sort()
keep_frames = []
for f in os.listdir(images_dir):
m = re.match(r"frame_(\d+)\.png", f)
if m:
keep_frames.append(int(m.group(1)))
keep_frames.sort()
keep_set = set(keep_frames)
deleted = [n for n in all_frames if n not in keep_set]
print("\n===== 帧统计 =====")
print(f"原视频总帧数: {len(all_frames)}")
print(f"保留帧数: {len(keep_frames)}")
print(f"删除帧数: {len(deleted)}")
if not deleted:
return [], all_frames, keep_frames, deleted
ranges = []
start = deleted[0]
prev = deleted[0]
for n in deleted[1:]:
if n == prev + 1:
prev = n
else:
ranges.append((start, prev))
start = n
prev = n
ranges.append((start, prev))
print("\n===== 删除的连续帧区间 =====")
for s, e in ranges:
print(f" - 从 {s} 到 {e} （共 {e - s + 1} 帧）")
return ranges, all_frames, keep_frames, deleted
def build_video_select(ranges):
parts = []
for s, e in ranges:
parts.append(f"between(n,{s-1},{e-1})")
return "not(" + "+".join(parts) + ")"
def build_audio_select(ranges, fps):
parts = []
for s, e in ranges:
t1 = (s - 1) / fps
t2 = (e - 1) / fps
parts.append(f"between(t,{t1},{t2})")
return "not(" + "+".join(parts) + ")"
def get_fps(ffmpeg, input_video):
cmd = [ffmpeg, "-i", input_video]
p = subprocess.Popen(cmd, stderr=subprocess.PIPE, stdout=subprocess.PIPE, text=True)
out, err = p.communicate()
fps_match = re.search(r"(\d+(?:\.\d+)?) fps", err)
fps = float(fps_match.group(1)) if fps_match else 30.0
print("\n原视频帧率 =", fps)
return fps
def get_frame_count(ffprobe, video_path):
cmd = [
ffprobe,
"-v", "error",
"-select_streams", "v:0",
"-count_packets",
"-show_entries", "stream=nb_read_packets",
"-of", "csv=p=0",
video_path
]
result = subprocess.run(cmd, capture_output=True, text=True)
try:
return int(result.stdout.strip())
except:
return None
def main():
ffmpeg = r".\ffmpeg-2026-01-29-git-c898ddb8fe-full_build\bin\ffmpeg.exe"
ffprobe = r".\ffmpeg-2026-01-29-git-c898ddb8fe-full_build\bin\ffprobe.exe"
input_video = "videoplayback.mp4"
output_video = "video_cut.mp4"
images_dir = "images" # 这个是删过帧只保留了人物画面的文件夹
images2_dir = "images2" # 这个是原始的所有帧的文件夹
ranges, all_frames, keep_frames, deleted = find_deleted_ranges(images_dir, images2_dir)
if not ranges:
return
fps = get_fps(ffmpeg, input_video)
video_select = build_video_select(ranges)
audio_select = build_audio_select(ranges, fps)
print("\n===== 视频过滤表达式 =====")
print(video_select)
print("\n===== 音频过滤表达式（按时间） =====")
print(audio_select)
cmd = [
ffmpeg,
"-i", input_video,
"-vf", f"select='{video_select}',setpts=N/({fps}*TB)",
"-af", f"aselect='{audio_select}',asetpts=N/SR/TB",
"-c:v", "libx264",
"-c:a", "aac",
"-pix_fmt", "yuv420p",
"-y",
output_video
]
print("\n===== 开始裁剪视频（含音频） =====")
subprocess.run(cmd)
print("\n完成！输出文件：", output_video)
actual_frames = get_frame_count(ffprobe, output_video)
print("\n===== 裁剪后帧数验证 =====")
print(f"预期保留帧数: {len(keep_frames)}")
print(f"实际视频帧数: {actual_frames}")
if actual_frames == len(keep_frames):
print("✔ 帧数完全一致，音视频同步裁剪成功")
else:
print("✘ 帧数不一致，请检查源数据")
if __name__ == "__main__":
main()
