Introduction and History In spring 2010 I have done some experiments with decrypted Wii ISO images. The data of encrypted ISO images looks like random data. Because of this effective compressing (with 7Z, RAR, BZIP2.) is not possible.

The compressors only reduce the size of the holes (= data areas). Manage such holes with the result of smaller files than the compressed ones. But decrypted images are good for compression. Additional it is possible to ignore the reproducible HASH values (3% of image size). In August 2010 I have remembered these ideas and I have begun to develop the file format WIA. First it was more a proof of concept to find out a format that reduce the needed disc space and can be handled with my tools directly. The disc data is stored in peaces (chunks) of a multiple of 2 MiB. Download Ustadz Cepot Lucu.

Each chunk is compressed (with BZIP2 or LZMA) independent from the other chunks. This allows random access reading. My first choice was BZIP2: It is good because it works already in chunks between 100KB and 900KB. The resulting WIA file is about 10%.

Recovery records make files compressed with rar resistant to corruption so if you download a Wii iso and during the downloading of the rar there are some minor. 1 Super Mario Galaxy Nintendo Action. 2 Metroid Prime 3: Corruption Action. 3 Super Smash Bros. 4 Mario Kart Wii Driving. 5 Wii Fit Sports. Torrent Contents [Wii]Mario_Kart[PAL][ISO-Full].rar 4,420 MB; Please note that this page does not hosts or makes available any of the listed filenames.

40% smaller than the WDF file. The original ISO can be restored from WIA completly including HASH errors.

The disadvantage of WIA is the multiple time needed for writing and reading. In a second step I take the from the and implement the compression methods LZMA and LZMA2. Both produce smaller WIA images than BZIP2. There are 2 more compression methods: NONE and PURGE. Both do not really compress the data, but they prepare the data for an external packer.

This combination is the most effektive packing method, but the best internal mode ( BEST = LZMA.7@50) have similar packing rates. WIA is the slowest supported data format. If compression is done with mode BEST the images are about 15-50% smaller than the same file in. If copying a WIA file to any other format the new file is a 1:1 copy of the original source.

Bad hash values are stored to guarantee the 1:1 copy. For discs this is only true for non scrubbed sectors. USB loaders will never use WIA because of the complex structure of WIA and the needed main memory for decompression. The Secret Kingdom Pat Robertson Pdf Converter. 1.1 Some statistics Here are some compression statistics.

The tests have run in 2010 on a Linux system with a AMD Athlon(tm) II X2 235e Processor, 2.7GHz. The test system was almost idle. The percent value is the compression rate against the format. The size of a compressed plain ISO with an external packer is similar (a little bit larger) to the size of a WDF.

The time values are the time needed for the compression (converting from WDF to WIA) and decrompression (converting from WIA to WDF). The source images are scrubbed WDF files and only data partitions are copied. Size creation read compr. 1.2 Compression rates The follwong table shows the compression rates and the resulting size for the game Super Mario Galaxy 2 (SB4P01) compressed with different variants. The first part shows the result of the scrubbed image, the second part of the raw image. The percent value is the compression rate against the format. Some image are compressed with an external packer after the conversion.

The tests are done on a Linux system with an AMD quad core (2.2GHz) and 7zip used 2 CPUs for compressing. Size scrubbed storing post total in bytes% or raw mode compr.

2.1 Compression methods When creating a WIA the data is split into chunks: Data of selected sectors (all if is set, else) are stored 1:1. The hash values are removed if they can be calculated from the source.

In a second step theses chunks will be compressed by one of the following methods: --compression NONE No compression is done. This format is very good for an external packer. Nearly no management data and hash values for the chunks are stored. Compression levels are not supported and the default chunk factor is 20 (chunk size 40 MiB). --compression PURGE Data is purged like WDF: Areas with zeros are detected and skipped.

The image is smaller than 'NONE' but contains more management info. There is a SHA1 hash for each data chunk so that data errors can be noticed. Compression levels are not supported and the default chunk factor is 20 (chunk size 40 MiB). This is more an experimental mode. --compression BZIP2 Each chunk is compressed with BZIP2.