# ffmpeg 大全
## 剪輯影片片段 10:00 至 15:00

ffmpeg -i src.mp4 -ss 00:10:00 -t 00:05:00 -acodec copy -vcodec copy dst.mp4 
ffmpeg -i src.mp4 -ss 00:10:00 -to 00:15:00 -acodec copy -vcodec copy dst.mp4 

## make video by images

## water mark
### make water mark png of ag roi

import numpy as np
import cv2


VIDEO_WIDTH = 1920
VIDEO_HEIGHT = 1080

shape = (VIDEO_HEIGHT, VIDEO_WIDTH, 3)
empty_frame = cv2.imread("/home/ubuntu/Desktop/aeaa.jpg")
empty_frame = np.zeros(shape, dtype=np.uint8)

x1=0.2128787878787879
x2=0.7583333333333333
y1=0.020188425302826378
y2=0.423956931359354



xl=VIDEO_WIDTH*x1 
xr=VIDEO_WIDTH*x2
yt=VIDEO_HEIGHT*y1 
yb=VIDEO_HEIGHT*y2

m = int(360*VIDEO_WIDTH/2688)

start_w = (xr-xl)
start_h = (yb-yt)*0.8
start_yb = (yt+(yb-yt)*0.8)  
end_yt = (yt+(yb-yt)*0.6)
end_xl=xl-m
end_xr=xr+m
end_w=end_xr-end_xl 
end_h=yb-end_yt

end_xl = (end_xl if (end_xl > 0) else 0)
end_yt = (end_yt if (end_yt > 0) else 0)
end_w =  (VIDEO_WIDTH-end_xl if (end_xl+end_w > VIDEO_WIDTH) else end_w)
end_h =  (VIDEO_HEIGHT-end_yt if (end_yt+end_h > VIDEO_HEIGHT) else end_h)

 
def draw_rectangle(img, x, y, w, h, color):
    left_up = (x, y)
    right_down =  (x+w, y+h)
     # red
    thickness = 2 
    cv2.rectangle(img, (int(x), int(y)), (int(x+w), int(y+h)), color, 2)

    # cv2.rectangle(img, (125, 20), (175, 40), (255, 0, 255), -1) 

    return img
print("(shape, xl, yt, start_w, start_h)", shape, xl, yt, start_w, start_h)
xxx = draw_rectangle(empty_frame, xl, yt, start_w, start_h, (0, 255, 0))
xxx = draw_rectangle(empty_frame, end_xl, end_yt, end_w, end_h, (255, 0, 250))

bgr = xxx
gray = cv2.cvtColor(bgr, cv2.COLOR_BGR2GRAY)

alpha = gray>0
print(alpha.sum())
ones = np.ones(gray.shape, np.uint8)
ones[alpha] = 255
ones[alpha==False] = 0
result = np.dstack([bgr, ones])
cv2.imwrite( "aeaa.jpg", bgr)
cv2.imwrite( "aeaa.png", result)

ffmpeg -i /mnt/video2/2020_Kbro/aeaa3652efcc42bfadfc4a56af988515/concat/01-22/frame_aeaa_0122.mp4 -i /mnt/video2/2020_Kbro/aeaa3652efcc42bfadfc4a56af988515.png -filter_complex "overlay=W-w:H-h" -b:v 6000K /mnt/video2/2020_Kbro/aeaa3652efcc42bfadfc4a56af988515/concat/01-22/frame_aeaa_0122_roi.mp4 -y &
ffmpeg -i /mnt/video2/2020_Kbro/d60bd7d598394f3f909120b5b52a35e6/concat/01-22/frame_d60b_0122.mp4 -i /mnt/video2/2020_Kbro/d60bd7d598394f3f909120b5b52a35e6.png -filter_complex "overlay=W-w:H-h" -b:v 6000K /mnt/video2/2020_Kbro/d60bd7d598394f3f909120b5b52a35e6/concat/01-22/frame_d60b_0122_roi.mp4 -y &
ffmpeg -i /mnt/video2/2020_Kbro/fb51b9a2aabf4f8da34651c9369195eb/concat/01-22/frame_fb51_0122.mp4 -i /mnt/video2/2020_Kbro/fb51b9a2aabf4f8da34651c9369195eb.png -filter_complex "overlay=W-w:H-h" -b:v 6000K /mnt/video2/2020_Kbro/fb51b9a2aabf4f8da34651c9369195eb/concat/01-22/frame_fb51_0122_roi.mp4 -y &




ffmpeg -i frame_aeaa_0121.mp4 -i aeaa.png -filter_complex "overlay=W-w:H-h" -framerate 15 -b:v 10000K test2.mp4

#### 期間增加浮水印:

ffmpeg -i input.mp4 -i image.png \
-filter_complex "[0:v][1:v] overlay=25:25:enable='between(t,0,20)'" \
-pix_fmt yuv420p -c:a copy \
output.mp4

## concate videos:

cat mylist.txt
file '/path/to/file1'
file '/path/to/file2'
file '/path/to/file3'
    
ffmpeg -f concat -safe 0 -i mylist.txt -c copy output.mp4