#Ecm tools what are code#

The ECM2 format keeps the sectors data in header, so just reading that data you can generate an index to seek in file very fast. That makes the file unseekable or at least very hard to be seeked, and that is why my program was created. The problem is that original ecm tool process the file without a clear block separation, storing the sectors info scattered in file. I was using it for a long time to store my CDROM images collection. The original program created by Neill Corlett is a very good tool. You can find more info in the CDROM Rainbow books Why I have created this 'Reloaded' version On the decoding process the program will generate that data again and then the image file will be exactly like the original (checked using MD5, SHA1.). This data is generated during the burn process and can be easily generated using an algorithm, and like it is not usefull to keep the data outside a CDROM, can be removed.

#Ecm tools what are code#

Depending of the sector type, it may contains Error Detection Code and Error Correction Code data, which will help to the CDROM drive to detect and recover a sector if it is damaged (for example by dust or even little scratches).

Contains a sectors TOC in header and sectors sizes are constant, so it can be easily indexed.Д¬hangelog can be viewed in CHANGELOG.md file FAQ How this program worksД¬DROM data is splitted in sectors, and those sectors are of 2352 bytes size.

Internal zlib, lzma, lz4 and FLAC compressions to do not depend of external tools.

A bit faster encoding/decoding: About 8s to encode or decode the FFVIII Disk 1 vs 11-14s of the original ECM tool.

Detects automatically if some of the optimizations cannot be done in a lossless way, and disable the failing optimization (copy protections).

Optimizes almost all non data bytes from sectors (remove sync, addr, mode, 50% of flags, EDC and ECC).

Now it detects and removes GAP and Dummy sectors (zeroed data). Keep the output when the process has failed

Reduce the compression ratio butДЄdd a end of block mark every X sectors in a seekable file. UsageД®cmtool -i/-input cdimagefile -o/-output ecmfileД®cmtool -i/-input ecmfile -o/-output cdimagefileД®nables extreme compression mode for LZMA/FLAC (can be very slow)Д¬reate a seekable file. This maybe can be improved by using bigger blocks during the compression step, but will need more memory for the process. The Reloaded version improves notably the CDDA compression ratio thanks to the FLAC compression, but is similar to the Original ECM Tool + 7zip if the image doesn't contains any CDDA track (it is even a bit worst). The compression ratio if LZMA compressor was improved by the Original ECM Tool thanks to the removed data. Reloaded conversely removes the GAP data, so reduction ratio is improved a bit.ДЄbout the compressed versions, the 7zip standalone compression is as expected the worst of all. The CDDA tracks in Firebugs have caused a poor reduction ratio in original ECM tool because it keeps all the sectors. This tests were made using the original ECM tool made by Neill Colett, this ECM Tool Reloaded without compression (just EC removal), 7zip extreme compression, Original ECM tool + 7zip extreme compression and this ECM Tool Reloaded using its internal compression method (LZMA for data and FLAC for audio, both in extreme compression mode).ДЄs you can see, the ECM Tool Reloaded uncompressed size is improved a bit by removing more data and dummy sectors from the streams. This make possible to use FLAC compresison in an Audio stream, which compress much more than other compression methods like LZMA or ZLIB. ECM Tool Reloaded is also able to detect the stream type. In the v2 versions, internal compression was added and then external tools are not required anymore.

This tool is completely loossless, so original data can be recovered without problems. This will allow to read the data from it very fast, and also can be complemented with a compression tool like 7zip to reach higher compression ratios. This ECM Tool allows you to remove all recoverable data from CD-ROM sectors, reducing the image size about 20% without using compression (depending of sectors types).

** I recommend to use the latest version, because old versions can contains bugs or incompatible features ** Description