// SYSTEM AREA
  32768 - null
  
// VOLUME DESCRIPTOR
  // for each volume
    1 - Type (1=Primary, 255=Terminator)
    5 - Header (CD001)
    1 - Version (1)
    
    if (Type=Terminator){
      2041 - null
      }
    else if (Type=Primary){
      1 - null
      32 - System Identifier Name (padded with spaces)
      32 - Volume Identifier Name (padded with spaces)
      8 - null
      4 - Number of Blocks for all the Volume Data
      4 - Number of Blocks for all the Volume Data (BIG)
      32 - null
      2 - Number of Disks in this Volume
      2 - Number of Disks in this Volume (BIG)
      2 - This Disk Number
      2 - This Disk Number (BIG)
      2 - Logical Block Size (2048)
      2 - Logical Block Size (BIG) (2048)
      4 - Path Table Size
      4 - Path Table Size (BIG)
      4 - Little-Endian Path Table Offset [*2048]
      4 - null
      4 - Big-Endian Path Table Offset (BIG) [*2048]
      4 - null
      34 - Root Directory Entry {
        1 - Entry Length (34)
        1 - null
        4 - Extent Offset [*2048]
        4 - Extent Offset (BIG) [*2048]
        4 - Extent Length
        4 - Extent Length (BIG)
        7 - Date
        1 - File Flags
        1 - File Unit
        1 - Interleave Gap Size
        2 - Volume Sequence Number
        2 - Volume Sequence Number (BIG)
        1 - Filename Length (0)
        1 - Padding to a multiple of 2 bytes (" ")
        }
      1858 - Other Data
      }
    else {
      2041 - Unknown
      }
      
// DIRECTORIES
  // for each directory
    // for each entry in the directory
      1 - Entry Length
      1 - null
      4 - Extent Offset [*2048]
      4 - Extent Offset (BIG) [*2048]
      4 - Extent Length
      4 - Extent Length (BIG)
      7 - Date
      1 - File Flags (bit 1 means it points to a directory, rather than a file)
      1 - File Unit
      1 - Interleave Gap Size
      2 - Volume Sequence Number
      2 - Volume Sequence Number (BIG)
      1 - Filename Length (including terminator)
      X - Filename
      2 - Filename Terminator (";1")
      0-1 - Padding to a multiple of 2 bytes
      
    // NOTE: If the next entry is going to overflow the 2048-byte boundry (which will show entryLength=0), skip to the next 2048-byte offset and continue reading
    
// FILE DATA
  // for each file
    X - File Data
    0-2047 - Padding to a multiple of 2048 bytes

Ref: https://wiki.osdev.org/ISO_9660#The_Primary_Volume_Descriptor