PPT pictures can be obtained from multiple channels. Here are some common ways:

1. Public copyright picture library: There are some public copyright picture libraries that can provide free download or use pictures, such as Pixabay, Unsplash, Pexels, etc. These picture libraries provide high-definition, free, and copyright-free picture resources that are relatively reliable. You can choose the appropriate picture to download or use according to your needs.

2. Public material website: Some other public material websites, such as Iconfont, Alibaba vector library, etc., can also provide a variety of free picture materials, including vector, PNG, JPG and other formats. These material websites provide more materials, and you can choose the appropriate picture to download or purchase according to your needs.

3. Self-shooting or design: If you have certain photography, painting or design skills, you can also shoot or design the picture materials you need. This not only ensures that the picture style and theme meet your needs, but also improves the personalization of PPT production and adds personal characteristics to your work.

In short, no matter where you get the pictures from, you need to comply with copyright and legal regulations, respect the intellectual property rights of others, and do not infringe on the legitimate rights and interests of others. At the same time, you also need to pay attention to the style and theme of the pictures to match your PPT design style to improve the visual effect and communication effect of the PPT.