Screen capture from the three minutes and fifty four music video for Firework. Depicts Katy Perry with other people dancing amidst fireworks.

Official music video; screen capture self-taken.

Firework

Entire portion of a single frame.

Yes.

To give the reader an idea of the video's contents.

1. No free equivalent exists that would effectively identify the article's subject.
2. The image does not in any way limit the ability of the copyright owners to market or sell their product.
3. The image is only used once and is rendered in low resolution to avoid piracy.
4. The image has been published outside Wikipedia; see source above.
5. The image meets general Wikipedia content requirements and is encyclopedic.
6. The image meets Wikipedia's media-specific policy.
7. The image is used in the article wiki-linked in the section.
8. The image is significant in identifying the subject of the article, which is the song.
9. The image is used in the article section giving a visual description of Katy Perry in the music video of the song.
10. The image has a brief description that identifies the image, notes the source, and provides attribution to the copyright holder.

No. As a music video, the image is not replaceable by free content; any other image that shows the images from the music video would also be copyrighted, and any version that is not true to the original would be inadequate for identification or commentary.

The end of the music video reads "© 2010 Capitol Records", so they are likely the copyright holder. Use of the music video shot in the article complies with Wikipedia non-free content policy and fair use under United States copyright law as described above.