Overlaying Image on Video Reduces Video Resolution

Overlaying image on video reduces video resolution

You are setting your

layercomposition.renderSize = CGSize(width: UIScreen.main.bounds.width, height: UIScreen.main.bounds.height)

when it should be

layercomposition.renderSize = yourAsset.tracks(withMediaType: AVMediaTypeVideo)[0].naturalSize

What the first one does is set your resolution to your screen size and not the actual size of the original video. The 2nd one corrects it to setting the resolution of the original video.

Think of it this way - you don't want your resolution to be the size of your screen - that would be really small. You want it the size of some original video or the size of some commonly used video setting.

Overlaying a large image onto a small video like snapchat

You can pass the width and height of the output video.
by using pad attribute you can add a black area in the video if a video with height is small

ffmpeg -i intro-blur.mp4 -i 3.jpg -filter_complex "[0]scale=720:1280:force_original_aspect_ratio=decrease,pad=720:1280:(ow-iw)/2:(oh-ih)/2,setsar=1[backd],[backd][1]overlay" out_intro_blur.mp4

you can scale overlay image like "scale=1439x2559" here overlay image can be accessed by "[1]" if you want to scale overlay image you can use [1]scale=1439x2559[scaled_image] after that you can use [scaled_image] to overlay on video.

example below

ffmpeg -i intro-blur.mp4 -i 3.jpg -filter_complex "[0]scale=720:1280:force_original_aspect_ratio=decrease,pad=720:1280:(ow-iw)/2:(oh-ih)/2,setsar=1[backd],[1]scale=1439x2559[scaled_image],[backd][scaled_image]overlay" out_intro_blur.mp4

Overlay Image quality decreasing with every frame in Live Video Feed

It is happening at this line:

glasses = cv2.resize(glasses, (ew,eh), interpolation = cv2.INTER_AREA)

because you keep resizing the glasses up and down in size at every iteration overwriting the original, so the same pair of glasses gets made bigger, then smaller, then bigger.

---

Instead, you should start from the original, high-quality glasses rather than from the resized glasses from the previous frame. So, outside the loop, change this line:

glasses = cv2.imread('glasses.png', -1) 

to

origGlasses = cv2.imread('glasses.png', -1) 

---

And inside the loop, change this line:

glasses = cv2.resize(glasses, (ew,eh), interpolation = cv2.INTER_AREA)

to:

glasses = cv2.resize(origGlasses, (ew,eh), interpolation = cv2.INTER_AREA)

Bad quality when overlaying PNG with FFMpeg

Use the format overlay option to avoid the default conversion to yuv420p in overlay filter.

overlay=10:10:format=auto

See the overlay filter documentation for other accepted values.

---

Related Topics