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map.createvmp [2010/06/23 13:43] (current)
jochen created
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 +====== map.CreateVMP ======
 +===== Motivation =====
 +This method can be used to transfer a statistical map ([[xff - MAP format|MAP]]) from [[xff - FMR format|FMR]] space (where minimal smoothing is applied to the data) to the [[xff - VMP format|VMP format]] in normalized (ISO- / [[xff - VTC format|VTC]]) voxel space (and, potentially,​ from there to [[xff - SMP format|SMP format]] in surface space) in BrainVoyager QX.
 +===== Requirements =====
 +You need:
 +  * one (or multiple) [[xff - MAP format|MAP]] object(s) containing the statistical map(s) you wish to display on a [[xff - VMR format|VMR]] (or [[xff - SRF format|SRF]])
 +  * the initial alignment ([[xff - TRF format|IA.trf]]) and fine alignment (''​FA.trf''​) files
 +  * if you wish to visualize the data on either the ''​ACPC.vmr''​ or the ''​TAL.vmr'',​ you also need the ''​ACPC.trf''​ and [[xff - TAL format|ACPC.tal]] files
 +  * further, if you wish to visualize this data on a surface (SRF), you also need the TAL-transformed SRF object
 +===== Method reference ('​map.Help('​CreateVMP'​)'​) =====
 +<​file>​ MAP::​CreateVMP ​ - create VMP from FMR based MAP object
 + ​FORMAT: ​      vmp = map.CreateVMP(fmr,​ afs [, vmpfile, meth, res, bb, o])
 + Input fields:
 +       ​fmr ​        FMR object matching MAP
 +       ​afs ​        cell array with alignment files, {ia, fa, acpc, tal}
 +       ​vmpfile ​    ​target VMP filename, if not given: unsaved
 +       ​meth ​       interpolation,​ '​nearest',​ {'​linear'​},​ '​cubic'​
 +       ​res ​        VMP resolution, default: 1
 +       ​bb ​         bounding box, default: small TAL box
 +       ​o ​          ​optional struct with settings
 +        .df        degrees of freedom, 1x1 or 1x2 DF setting
 + ​Output fields:
 +       ​vmp ​        ​resulting VMP object</​file>​
 +===== Input fields (details) =====
 +==== fmr ====
 +The ''​fmr''​ input variable must be a valid [[xff - FMR format|FMR]] object, e.g. you can use the file selector of ''​xff''​ by using the syntax, ''​fmr = xff('​*.fmr'​);''​.
 +This is required as the [[xff - MAP format|MAP]] object on which the method is called does **not** contain the required spatial information about resolution, etc.!
 +==== afs ====
 +This is a cell array with the required transformation ([[xff - TRF format|TRF]] and [[xff - TAL format|TAL]]) objects. For example, you could use the following lines of code to create one such array:
 +<code matlab map_createvmp_getafs.m>​% request IA.trf
 +ia = xff('​*IA*.trf',​ '​Please select IA TRF file...'​);​
 +if isempty(ia) || ...
 +   ​~isxff(ia,​ '​trf'​)
 +    error('​No IA TRF file selected.'​);​
 +% request FA.trf
 +fa = xff('​*FA*.trf',​ '​Please select FA TRF file...'​);​
 +if isempty(fa) || ...
 +   ​~isxff(fa,​ '​trf'​)
 +    error('​No FA TRF file selected.'​);​
 +% request ACPC.trf
 +acpc = xff('​*ACPC*.trf',​ '​Please select ACPC file... (leave blank for ISO-voxel space)'​);​
 +% request TAL.trf (if ACPC is not empty)
 +if ~isempty(acpc)
 +    tal = xff('​*.TAL',​ '​Please select TAL file...'​);​
 +% compile afs cell array
 +if ~isempty(acpc)
 +    if ~isempty(tal)
 +        acpc = {acpc, tal};
 +    else
 +        acpc = {acpc};
 +    end
 +    acpc = {};
 +afs = {ia, fa, acpc{:​}};</​code>​
 +==== vmpfile ====
 +Either leave blank of give desired output filename of [[xff - VMP format|VMP object]] to be created.
 +==== meth ====
 +Interpolation method to use. For maximum quality (lowest smoothing between MAP and VMP), set to '''​cubic'''​ (or even '''​lanczos3'''​).
 +==== res ====
 +Depending on the resolution in the ''​FMR''​ (and ''​MAP''​),​ as well as the purpose for display (e.g. surface space), you might want to select an appropriate resolution. Eventually, using ''​1''​ (the default) will only cost performance during VMP creation and some additional disk space while ensuring that any additional interpolation (from VMP to SMP) does not introduce further smoothing.
 +==== bb ====
 +Bounding box to be used. This must be given in BrainVoyager coordinate system (TAL axes order, however). For instance, the default bounding box is given as ''<​nowiki>​[59,​ 57, 52; 197, 231, 172]</​nowiki>'',​ which means that the X axis will be covered from 59 to 197 (in ''​.res''​ step size), which translates to TAL coordinates 69 through -69 (BrainVoyager'​s X axis runs into negative TAL X axis direction!) and so forth.
 +==== o ====
 +This is only to be used if the ''​MAP''​ object does not contain the correct degrees of freedom (DF1/DF2) parameter. To override the settings in the ''​MAP''​ (e.g. the statistic therein is an F-map), use the following syntax: ''<​nowiki>​o = struct('​df',​ [3, 140]);</​nowiki>''​ for (3, 140) being the DF.
 +===== Complete syntax example =====
 +This example assumes the ''​afs''​ argument has been made already (see above!):
 +<code matlab map_createvmp_example>​% the following variables are being used and must exist
 +% - map: MAP object (fitting FMR!)
 +% - fmr: FMR object
 +% - afs: collection of TRF/TAL objects
 +% the following settings are used
 +% - no VMP filename (requires manual saving)
 +% - high quality interpolation (lanczos3)
 +% - 1mm resolution (best for going to SRF/SMP later)
 +% - large bounding box (covering ALL TAL space)
 +% - no df override
 +vmp = map.CreateVMP(fmr,​ afs, '',​ '​lanczos3',​ 1, [44, 44, 38; 212, 242, 194]);
map.createvmp.txt ยท Last modified: 2010/06/23 13:43 by jochen