Ps only extracts line drafts, not line drafts with patterns in them. The method is as follows:

1, mask line, step one, open a picture in PS, copy a layer in PS, then we use shortcut keys, press Ctrl+A to select all layers, press Ctrl+C to copy a layer of graphics, and then press Q to enter the quick mask. After entering the quick mask, the color bar will turn white.

2. Use the channel to extract the line draft. First, open PS, drag a picture into PS to copy a layer of layers, and fill the background layer with white. Select the channel, hold down Ctrl and click RGB, then click Layer to return to the layer interface, and press Ctrl+D to eliminate the ant line, and you can extract the draft line.