$ fq 'first(grep_by(.type == "elst"))' file.mp4
     |00 01 02 03 04 05 06 07 08 09|0123456789|.boxes[3].boxes[1].boxes[1].boxes[0]{}: box
0xd5c|                           00|         .|  size: 28
0xd66|00 00 1c                     |...       |
0xd66|         65 6c 73 74         |   elst   |  type: "elst" (An edit list)
0xd66|                     00      |       .  |  version: 0
0xd66|                        00 00|        ..|  flags: 0
0xd70|00                           |.         |
0xd70|   00 00 00 01               | ....     |  entry_count: 1
0xd70|               00 00 00 28 00|     ...(.|  entries[0:1]:
0xd7a|00 00 00 00 01 00 00         |.......   |
