Video generation method and apparatus, device and readable storage medium

A video generating apparatus, comprising:

• at least one processor and a memory, wherein
• the memory stores computer executable instructions, and
• the at least one processor executes the computer executable instructions stored in the memory to:
• acquire a source image;
• generate a plurality of sketch images according to the source image, wherein the plurality of sketch images respectively correspond to sketch images of the source image at different color depths;
• generate a plurality of subgraphs of a target sketch image based on the target sketch image, wherein the plurality of subgraphs respectively correspond to sketch images of the target sketch image at different drawing completion degrees, and the target sketch image is any sketch image of the plurality of sketch images;
• take respective subgraphs of respective sketch images in the plurality of sketch images as video frames of a sketch drawing video, set an order of the video frames according to an order of color depth from light to dark and an order of drawing completion degrees from low to high, and generate the sketch drawing video;
• and
• determine an increase order of mask values of pixels in a first mask, wherein initial mask values of the pixels in the first mask are 0, an increase of the pixels in the first mask is used to indicate that the mask values of the pixels are changed from 0 to 1, and the first mask is used for gradually transforming a background of the target sketch image into the target sketch image according to the increase order;
• and generate the plurality of subgraphs according to the increase order, the target sketch image and the background of the target sketch image, wherein each increase in the increase order and a subgraph in the plurality of subgraphs are in a one-to-one correspondence.