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Old 26 November 2021, 19:56   #200
Crashdisk
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Join Date: Jun 2009
Location: France
Age: 46
Posts: 1,995
Answer to a question I was asked about the flags displayed when decompressing a DMS file.
Code:
File selected             : FWR3UPD.DMS
File size                 : 744.343 bytes
CRC32                     : $BB0CA619
File loaded as an DMS     : DMS Archive

File format               : DMS hacked with MaPuS
Version number of creator : v2.04
Version needed to extract : v1.11
Packed bytes              : 29.940.292 bytes
Unpacked bytes            : 36.495.360 bytes
Lowtrack in archive       : 00
Hightrack in archive      : 00
Compression Mode Used     : Heavy1
Creation date             : 1994.12.15 07:15:04
Time to create archive    : 00:01:36
Info Header CRC           : $5D9F

Machine Type              : Amiga
Machine CPU               : Motorola 68030
CPU Coprocessor           : Motorola 68882
Kickstart Version used    : 40.68
Disktype of Archive       : Amiga OS 1.0 OFS
General info              : Appends DMS_DEV_Fixed 

  Cyl    Dec Len   RLE Len  Comp Len  C.Mode & Flag  U.SUM  D.CRC  H.CRC  Crypt
------  --------  --------  --------  -------------  -----  -----  -----  -----
Banner     3.308         -         -  NoComp  - - -  $048D  $F640  $09AD     No
 FakBB     1.024         -         -  NoComp  - - -  $C936  $D585  $193C     No
   C00    11.264    10.998    10.144  Heavy1  - T -  $5357  $BF15  $586B     No
   C01    11.264    11.134    10.721  Heavy1  - T C  $1EDA  $9CD7  $465B     No
   C02    11.264         -    10.871  Heavy1  D T C  $E992  $75DA  $025A     No
First of all, this only concerns cylinders compressed in HEAVY mode, so potentially DMS created from 1.11 version.
D > Typically, the raw data is pre-compressed with the RLE method before applying the Heavy method. This flag indicates that the data is directly compressed in Heavy.
T > This flag indicates that the compressed data starts with a literal table.
C > This flag indicates that the data is compressed individually from the others. Generally, the compressed data of a cylinder X depends on the data from the decompression of cylinder X-1. If this flag is set, the cylinder can be read without having to decompress the previous data. This is only used with the DEVFIX option (for use with DMSDevice)
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