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='''ResMed Data Format (excluding S8 models)'''=
This page was originally written by Mark Watkins, during the initial build of the SleepyHead program. It needs change in approach, or should be taken as "history".

==Data format analysis==

Grade: C (extra points awarded for being open)

'''Negatives''' 
* Only keeps basic summary data when the card is left out. NO graphs. 
* Unnecessarily deletes high-res flow waveform data after 7 days, all other graphs after 30 days.
* Summary does not contain settings info for each session, only once per day, according to ResMed split, which is not suitable for night-owls.
* Evil SDcard "drift" problem, which causes Events to NOT sync well over flow waveform. Needs a regular card format to work around this.
* Bloaty data format.

'''Positives'''
* Manufacturer chose to use an industry-standard data format.
* Reasonable assortment of data available, and at a decent resolution.

= Data Format =
ResMed chose an intelligent and sensible approach when designing their machines, they used an industry standard. (Thankyou ResMed for showing common sense!)

'''EDF+ Format'''<br />
ResMed uses the European Data Format Plus format. This format is documented [http://www.edfplus.info here]. It is rather verbose, but sensibly designed.. The Event Annotations are a little tricky.

= ResMed SDCard Folder Structure =
 <nowiki>
[DATALOG]            Folder containing all the session data
[SETTINGS}           Folder with machine settings
Identification.crc   Checksum info
Identification.tgt   Machine identification data
Journal.dat          tbd
STR.crc              Checksum info
STR.edf              All overall summary information</nowiki>

= Analysis of folders and files =
==Identification.tgt==
This file holds an extensive number of data and parameters of the machine. These are shown here in the same fixed order as in the file.

{| class="wikitable"
|-
! Code !! Remark !! Explanation !! Example
|-
| #IMF|| All later models || TBD || #IMF 0001
|-
| #VIR|| All later models|| TBD || #VIR 0064
|-
| #RIR|| All later models|| TBD || #RIR 0064
|-
| #PVR|| All later models|| TBD  || #PVR 0064
|-
| #PVD|| All later models|| TBD || #PVD 000F
|-
| #CID|| All later models|| TBD || #CID CX040-044-018-015-100-100-100
|-
| #RID|| All later models|| TBD  || #RID 0012
|-
| #VRN|| Only S9 Models || TBD || #VRN 20142455118
|-
| #VPC|| Only S9 Models|| TBD || #VPC 3688P
|-
| #NID|| Only S9 Models|| TBD || #NID 0001
|-
| #VID || All Models || TBD || #VID 002C
|-
| #SRN|| All Models|| Serial number || #SRN 22182060837
|-
| #SID|| All Models || Serial ID?|| #SID SX584-0201
|-
| #RID|| Only S9 Models || TBD || #RID 0064
|-
| #PNA || All Models || Part Name|| #PNA Lumis_VPAP_150_ST
|-
| #PCD|| All Models || TBD || #PCD 28328
|-
| #PCB|| All Models || Printed Circuit Board number? || #PCB (90)R280-776(91)T3(21)89180702
|-
| #MID|| All Models || TBD || #MID 0028
|-
| #FGT|| All Models || TBD || #FGT 28_M40_V44
|-
| #BID|| All Models || TBD || #BID SX585-0100
|}

== DATALOG Folder ==
The main data is stored in 4 EDF files per session, with each file name consisting of a date, time, and type, followed by .edf

There is also a .crc (checksum) file for each of the above, but they are not needed to parse the data.

==== Example ====
 <nowiki>20110601_021922_EVE.edf
(date)_(time)_(type).edf</nowiki>

==== The 4 File Types ====
 <nowiki>Type  Details
EVE    Event annotation data
BRP    High resolution graph data 
SAD    Pulse oximetry data
PLD    Low resolution graph data</nowiki>

=== File Type Notes ===

'''Note:''' Some foreign language machines use a different set of signal codes in the EDF data.

==== EVE Event Annotation Data ====
The S9 series flags the following events:
*Hypopnea
*Apnea
*Obstructive Apnea
*Central Apnea

==== BRP High resolution graph data ====
 <nowiki>
Code            Details                        Units                            Notes
"Flow"          Flow Rate                      ?
"Mask Pres"     High-res Mask Pressure         cmH2O
"Resp Event"    Respiratory Event              ?                                VPAP</nowiki>

==== SAD Pulse Oximetry data ====
 <nowiki>
Code            Details                        Units                            Notes
"Pulse"         Pulse Rate                     Beats per minute
"SpO2"          SpO2 (Oxygen Saturation)       % Saturation</nowiki>

The oximetry device that records this information is hideously expensive, notoriously unreliable, and ResMed should be ashamed for releasing it.

==== PLD Low resolution graph data ====

'''Signal List'''
 <nowiki>
Code            Details                        Units                            Notes
"Snore Index"   Snore Index                    ??
"Therapy Pres"  Therapy Pressure               cmH2O
"Insp Pres"     IPAP / Inspiratory Pressure    cmH2O
"MV"            Minute Ventilation             ?
"RR"            Respiratory Rate               Breaths per Minute
"Vt"            Tidal Volume                   ?
"Leak"          Leak Rate                      L/Second (I convert to L/Min)
"FFL Index"     Flow Limitation Index          ?
"Mask Pres"     Low-res Mask Pressure          cmH2O
"Exp Pres"      EPAP / Expiratory Pressure     cmH2O
"I:E"           Inspiratory : Expiratory Ratio ?                                VPAP
"Ti"            Ti??                           ?                                VPAP
"Te"            Te??                           ?                                VPAP
"TgMV"          Target Minute Ventialation     ?                                ASV Machines
""              Unknown Empty                  ?
""              Unknown Empty                  ?</nowiki>

most ? fields are known, I just have to look them up again..?? fields really are unknown (to me).

The two empty signals always appear at the end. not entirely sure of their purpose.

== SETTINGS Folder ==
The Settings folder holds a number of log (.log) files and settings (.tgt) files, each with its own .crc (checksum) file.

== STR.edf File ==

This file contains a summary database in EDF format. It contains things like AHI indexes, 95% values, etc...

There is only one copy, in the root directory of the SD-card, and it is updated at the end of a session.



Most records contain one entry per day.

SleepyHead doesn't need much of it, as it provides it's own indexing..

It does contain some data not available elsewhere, most notably EPR data.

== ResMed S9 Storage Gotchas ==

The S9 continuously erases older data to keep the card from overflowing:

* BRP data older than 7 days.
* PLD data older than 30 days.
* Everything older than 365 days.

Regularly backup copies of your SD card to work around this!

= SleepyHeads Implementation =
SleepyHeads EDF parser and S9 importer has been written from scratch

It consists of two parts
* A generic EDF parser class named '''EDFParser'''
* and the custom S9 importer class named '''ResMedLoader'''

It is implemented in SleepLib/loader_plugins/resmed_loader.cpp / .h

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