| 1 |
nslice |
number of slices (planes) in volume (=1 for an image) |
| 2 |
nrow |
number of rows per slice. |
| 3 |
irec |
total number of records (including header records) in each image of a simple image or stacked image file. |
| 4 |
nhistrec |
(obsolete, unused) |
| 5 |
iform |
file type specifier. Obsolete file types d, 8, 11, 12, 16, -1, -3, -7, and -9 are no longer supported in SPIDER.
| iform | (type) | data type |
| 1 | (r) | 2D image. |
| 3 | (r) | 3D volume. |
| -11 | (fo) | 2D Fourier, mixed radix odd. |
| -12 | (fe) | 2D Fourier, mixed radix even. |
| -21 | (fo) | 3D Fourier, mixed radix odd. |
| -22 | (fe) | 3D Fourier, mixed radix even. |
|
| 6 |
imami |
maximum/minimum flag. Is set at 0 when the file is created, and at 1 when the maximum, minimum, average, and standard deviation have been computed and stored into this header record (see following locations). |
| 7 |
fmax |
maximum value. |
| 8 |
fmin |
minimum value. |
| 9 |
av |
average value. |
| 10 |
sig |
standard deviation. A value of -1.0 indicates that sig has not been computed previously. |
| 11 |
ihist |
(obsolete, no longer used). |
| 12 |
nsam |
number of pixels per line. |
| 13 |
labrec |
number of records in file header (label). |
| 14 |
iangle |
flag that tilt angles are present. |
| 15 |
phi |
tilt angle. |
| 16 |
theta |
tilt angle. |
| 17 |
gamma |
tilt angle (also called psi). |
| 18 |
xoff |
x translation. |
| 19 |
yoff |
y translation. |
| 20 |
zoff |
z translation. |
| 21 |
scale |
scale factor. |
| 22 |
labbyt |
total number of bytes in header. |
| 23 |
lenbyt |
record length in bytes. |
| 24 |
istack |
This position has a value of 0 in simple 2D or 3D (non-stack) files. In an "image stack" there is one overall stack header followed by a stack of images in which each image has its own image header. (An image stack differs from a simple 3D image in that each stacked image has its own header.) A value of >0 in this position in the overall stack header indicates a stack of images. A value of <0 in this position in the overall stack header indicates an indexed stack of images and gives the maximum image number allowed in the index. |
| 25 |
NOTUSED |
This position is unused now! Prior to release 9.0, a -1 at this location in an overall stack indicated a valid stack and in the stacked images, a value of 1 indicated that this image was in use (existed). |
| 26 |
maxim |
This position is only used in the overall header for a stacked image file. There, this position contains the number of the highest image currently used in the stack. This number is updated, if necessary, when an image is added or deleted from the stack. |
| 27 |
imgnum |
This position is only used in a stacked image header. There, this position contains the number of the current image or zero if the image is unused. |
| 28 |
lastindx |
This position is only used in the overall header of indexed stacks. There, this position is the highest index currently in use. |
| 29 |
unused |
|
| 30 |
unused |
|
| 31 |
Kangle |
flag that additional angles are present in header. 1 = one additional rotation is present, 2 = additional rotation that preceeds the rotation that was stored in words 15..20. |
| 32 |
phi1 |
|
| 33 |
theta1 |
|
| 34 |
psi1 |
|
| 35 |
phi2 |
|
| 36 |
theta2 |
|
| 37 |
psi2 |
|
| 50-76 |
|
reserved for Jose Maria's transforms |
| 212-214 |
cdat |
character * 11 containing creation date e.g. 27-MAY-1999 |
| 215-216 |
ctim |
character * 8 containing creation time e.g. 09:43:19 |
| 217-256 |
ctit |
character * 160 containing title |
Raw image data follows.
A file with the default extension .spi can be loaded by just double clicking on the file in the open file dialog box. Files with
another extension, which are in a spider format can be loaded by right clicking on the file in the dialog box and choosing
Format from the popup menu. In the file format chooser select "Spider Format" and press OK. Press the Open Button in the open file dialog
box.
