# gm convert -size 4x4 'xc:#000' 'xc:#fff' 4x4.gif
$ fq -d gif dv 4x4.gif
    |00 01 02 03 04 05 06 07 08 09 0a 0b 0c 0d 0e 0f|0123456789abcdef|.{}: 4x4.gif (gif) 0x0-0x5f (95)
0x00|47 49 46 38 39 61                              |GIF89a          |  header: "GIF89a" (valid) 0x0-0x6 (6)
0x00|                  04 00                        |      ..        |  width: 4 0x6-0x8 (2)
0x00|                        04 00                  |        ..      |  height: 4 0x8-0xa (2)
0x00|                              f0               |          .     |  gcp_follows: true 0xa-0xa.1 (0.1)
0x00|                              f0               |          .     |  color_resolution: 8 0xa.1-0xa.4 (0.3)
0x00|                              f0               |          .     |  zero: 0 0xa.4-0xa.5 (0.1)
0x00|                              f0               |          .     |  bit_depth: 1 0xa.5-0xb (0.3)
0x00|                                 00            |           .    |  black_color: 0 0xb-0xc (1)
0x00|                                    00         |            .   |  pixel_aspect_ratio: 0 0xc-0xd (1)
    |                                               |                |  global_color_map[0:2]: 0xd-0x13 (6)
    |                                               |                |    [0][0:3]: color 0xd-0x10 (3)
0x00|                                       00      |             .  |      [0]: 0 r 0xd-0xe (1)
0x00|                                          00   |              . |      [1]: 0 g 0xe-0xf (1)
0x00|                                             00|               .|      [2]: 0 b 0xf-0x10 (1)
    |                                               |                |    [1][0:3]: color 0x10-0x13 (3)
0x10|00                                             |.               |      [0]: 0 r 0x10-0x11 (1)
0x10|   00                                          | .              |      [1]: 0 g 0x11-0x12 (1)
0x10|      00                                       |  .             |      [2]: 0 b 0x12-0x13 (1)
    |                                               |                |  blocks[0:5]: 0x13-0x5e (75)
    |                                               |                |    [0]{}: extension_block 0x13-0x1b (8)
0x10|         21                                    |   !            |      introducer: 33 0x13-0x14 (1)
0x10|            f9                                 |    .           |      function_code: "GraphicalControl" (0xf9) 0x14-0x15 (1)
    |                                               |                |      func_data_bytes[0:1]: 0x15-0x1b (6)
    |                                               |                |        [0]{}: func_data_byte 0x15-0x1b (6)
0x10|               04                              |     .          |          byte_count: 4 0x15-0x16 (1)
0x10|                  00 00 00 00                  |      ....      |          data: raw bits 0x16-0x1a (4)
0x10|                              00               |          .     |          terminator: 0 0x1a-0x1b (1)
    |                                               |                |    [1]{}: extension_block 0x1b-0x2e (19)
0x10|                                 21            |           !    |      introducer: 33 0x1b-0x1c (1)
0x10|                                    ff         |            .   |      function_code: "Application" (0xff) 0x1c-0x1d (1)
    |                                               |                |      func_data_bytes[0:2]: 0x1d-0x2e (17)
    |                                               |                |        [0]{}: func_data_byte 0x1d-0x29 (12)
0x10|                                       0b      |             .  |          byte_count: 11 0x1d-0x1e (1)
0x10|                                          4e 45|              NE|          data: raw bits 0x1e-0x29 (11)
0x20|54 53 43 41 50 45 32 2e 30                     |TSCAPE2.0       |
    |                                               |                |        [1]{}: func_data_byte 0x29-0x2e (5)
0x20|                           03                  |         .      |          byte_count: 3 0x29-0x2a (1)
0x20|                              01 00 00         |          ...   |          data: raw bits 0x2a-0x2d (3)
0x20|                                       00      |             .  |          terminator: 0 0x2d-0x2e (1)
    |                                               |                |    [2]{}: image 0x2e-0x3f (17)
0x20|                                          2c   |              , |      separator_character: 44 0x2e-0x2f (1)
0x20|                                             00|               .|      left: 0 0x2f-0x31 (2)
0x30|00                                             |.               |
0x30|   00 00                                       | ..             |      top: 0 0x31-0x33 (2)
0x30|         04 00                                 |   ..           |      width: 4 0x33-0x35 (2)
0x30|               04 00                           |     ..         |      height: 4 0x35-0x37 (2)
0x30|                     00                        |       .        |      local_color_map_follows: false 0x37-0x37.1 (0.1)
0x30|                     00                        |       .        |      image_interlaced: false 0x37.1-0x37.2 (0.1)
0x30|                     00                        |       .        |      zero: 0 0x37.2-0x37.5 (0.3)
0x30|                     00                        |       .        |      bit_depth: 1 0x37.5-0x38 (0.3)
0x30|                        02                     |        .       |      code_size: 2 0x38-0x39 (1)
    |                                               |                |      image_bytes[0:1]: 0x39-0x3f (6)
    |                                               |                |        [0]{}: func_data_byte 0x39-0x3f (6)
0x30|                           04                  |         .      |          byte_count: 4 0x39-0x3a (1)
0x30|                              84 8f 09 05      |          ....  |          data: raw bits 0x3a-0x3e (4)
0x30|                                          00   |              . |          terminator: 0 0x3e-0x3f (1)
    |                                               |                |    [3]{}: extension_block 0x3f-0x47 (8)
0x30|                                             21|               !|      introducer: 33 0x3f-0x40 (1)
0x40|f9                                             |.               |      function_code: "GraphicalControl" (0xf9) 0x40-0x41 (1)
    |                                               |                |      func_data_bytes[0:1]: 0x41-0x47 (6)
    |                                               |                |        [0]{}: func_data_byte 0x41-0x47 (6)
0x40|   04                                          | .              |          byte_count: 4 0x41-0x42 (1)
0x40|      00 00 00 00                              |  ....          |          data: raw bits 0x42-0x46 (4)
0x40|                  00                           |      .         |          terminator: 0 0x46-0x47 (1)
    |                                               |                |    [4]{}: image 0x47-0x5e (23)
0x40|                     2c                        |       ,        |      separator_character: 44 0x47-0x48 (1)
0x40|                        00 00                  |        ..      |      left: 0 0x48-0x4a (2)
0x40|                              00 00            |          ..    |      top: 0 0x4a-0x4c (2)
0x40|                                    04 00      |            ..  |      width: 4 0x4c-0x4e (2)
0x40|                                          04 00|              ..|      height: 4 0x4e-0x50 (2)
0x50|80                                             |.               |      local_color_map_follows: true 0x50-0x50.1 (0.1)
0x50|80                                             |.               |      image_interlaced: false 0x50.1-0x50.2 (0.1)
0x50|80                                             |.               |      zero: 0 0x50.2-0x50.5 (0.3)
0x50|80                                             |.               |      bit_depth: 1 0x50.5-0x51 (0.3)
0x50|   ff                                          | .              |      code_size: 255 0x51-0x52 (1)
    |                                               |                |      local_color_map[0:2]: 0x52-0x58 (6)
    |                                               |                |        [0][0:3]: color 0x52-0x55 (3)
0x50|      ff                                       |  .             |          [0]: 255 r 0x52-0x53 (1)
0x50|         ff                                    |   .            |          [1]: 255 g 0x53-0x54 (1)
0x50|            00                                 |    .           |          [2]: 0 b 0x54-0x55 (1)
    |                                               |                |        [1][0:3]: color 0x55-0x58 (3)
0x50|               00                              |     .          |          [0]: 0 r 0x55-0x56 (1)
0x50|                  00                           |      .         |          [1]: 0 g 0x56-0x57 (1)
0x50|                     02                        |       .        |          [2]: 2 b 0x57-0x58 (1)
    |                                               |                |      image_bytes[0:1]: 0x58-0x5e (6)
    |                                               |                |        [0]{}: func_data_byte 0x58-0x5e (6)
0x50|                        04                     |        .       |          byte_count: 4 0x58-0x59 (1)
0x50|                           84 8f 09 05         |         ....   |          data: raw bits 0x59-0x5d (4)
0x50|                                       00      |             .  |          terminator: 0 0x5d-0x5e (1)
0x50|                                          3b|  |              ;||  terminator: 59 0x5e-0x5f (1)