Ray Tracing Box/RAY_CD.mdf/raytrace/dta/whatsnew.dta

Text File | 1994-01-18 | 44KB | 866 lines

What's new in DTA:

 Rel 2.1.0 (??/??/??)

  (
  I made some pretty substantial changes to the way DTA works,
  since 2.0.8.  Some things may still be broken.

  Some things that I'm sure are still broken are:
   o I haven't finished updating the documentation file,
     so this file will have to do.
   o DTA still doesn't read 16-color .PCX files.
  )

  Changes:
  o Fixed flic-reading code so it reads the bottom row of
    pixels properly.
  o Rewrote a lot of the internal picture-file handling code.
    All pictures are now read into memory buffers, and all
    operations are performed on the memory buffers in
    sequence.  (Formerly, DTA read most pictures
    in a line at a time, and did all the operations on
    each line of pixels... it kept lots of picture files
    open simultaneously )
    The side effects of these changes are:
     (1) Basic operations use more memory.
     (2) Real complicated operations (averaging, compositing,
         etc.) use less memory.
     (3) Most everything works at least a little bit faster,
         and some operations are a lot faster.
     (4) There's no longer any limit on the number of pictures
         that you can average.  (DTA used to fail if you
         tried averaging more than 10 or 12 pictures.)
     (5) I was able to reshuffle the order of operations.
         Now, the order is: chroma-key, averaging, clipping,
         scaling, post-scale clipping, rotation, compositing.
         (Now that I've gotten this far, I've realized that
         this still stinks... what's really needed is a
         user-defined order.)
     (6) Made it possible to add arbitrary rotations.
     (7) Processing a frame takes more steps, so the "percent
         finished" information isn't as useful as it used
         to be.
  o When building 8-bit flics, DTA used to always use the
    320x200 resolution some another resolution was selected
    using the /R switch.  The reason for that was that 320x200
    is the only supported resolution for the original Autodesk
    Animator .FLI format.
      From now on, it'll use the actual resolution from the
    first input picture file, like the now-obsolute /RA
    switch used to do.
      So unless your input pictures are already 320x200, you'll
    get .FLC files instead of .FLI files.  You can make DTA
    create a .FLI file even with other resolution input by
    specifying /R1 or /R320,200.
      You'll also need to use /R if you want to create
    larger images for compositing...
  o Reworked grayscale options... now there's /G, /G128, /G64,
    and /G32, /G16, /G8, and /G4.
      /G represents a 256-level grayscale except when the output
    format is a 320x200 .FLI file, when it represents a 64-level
    grayscale.  That's because .FLI won't support higher than
    64 shades.
      /G128 represents a 128-level grayscale, /G64 a 64-level
    grayscale, etc.
    The lower numbers will get you a lower-quality image, which
    will almost always compress better.
      Most VGA and SVGA monitors can only display 64 shades
    of gray, so it's wasteful to use more than that if your
    picture will only be displayed on a monitor.
    Some laptop VGA displays can only display 32 shades.
      If you're going to be printing your image or using it
    as a bump map or height field with a rendering program,
    then the more shades the better.
  o Renamed /CH (chroma-key) to /CK so that /CH would be free
    for a new option.
  o Got rid of /3D... I pulled it out to make some of the
    rewrite easier.  You can now get a similar 3d effect
    using /CHR and /CHB (see below).
  o Added /BU, which makes DTA save .TGA files bottom-up
    (or upside-down, if you prefer) instead of top-down.
    ... some applications don't understand top-down .TGAs.
  o Added /CH[R,G,B,A] which stand for CHannel insertion,
    which should let you create some truly weird effects
    if you're so inclined.
    (This is a pretty hard concept to explain, so bear with me...
    and remember that you don't have to use it, just like you
    don't have to use /L...  DTA still understands simple
    command lines like "dta *.tga".)
      You can specify /CHR (red channel), /CHG (green channel),
    /CHB (blue channel), and /CHA (alpha channel) to cause
    a gray-scale version of an image file to be inserted
    into a specific channel of the current layer.
      You can use this to specify a matte for an image that
    doesn't contain an alpha channel, like this:
        dta background.tga /l pics*.tga /cha masks*.tga
    or to get a red/blue 3d effect (the kind that requires
    funny glasses):
        dta /chr left*.tga /ga0.8 /chb right*.tga
    (the /ga is to adjust the brightness of the red component
     so it doesn't drown out the blues.  Some experimentation
     may be necessary to get the balance just right... if
     somebody comes up with an ideal brightness combination,
     let me know and I'll put it in the doc.)
      /CH works much like /L, except /CH is subordinate to /L.
      /CH merging (insertion) takes place after picture
    averaging, gamma correction, and chroma-keying, but before
    clipping, rotation, scaling, etc.  /L merging (compositing)
    takes place after all of the above.  So, you can have separate
    chroma-key, gamma, averaging settings for each /CH layer,
    but only one /ROT, /LOC, etc. setting in each /L layer
    regardless of how many /CH layers you've got.  And some
    other switches, like /F, /O, /R, etc. can only be specified
    once per command line, no matter how many /L and /CH layers
    you've got.
      Note that if you specify "pics*.tga /cha masks*.tga",
    you're really specifying two /CH levels, not just one.
    The first, without a /CH parameter, contains pics*.tga,
    and there's no special processing of the color channels.
    The second gets converted to a grayscale and is inserted
    into the alpha channel.
      (Thanks to John Jordan for suggesting alpha insertion in
    the first place...)
  o When converting from one file format to another, DTA
    will usually use the original picture's filename, but
    with a new extension (unless you specify a different
    filename with /O).
      But, if you're creating an output picture from multiple
    input layers, or multiple input channels, or averaged
    images, or if input file and output file are in the same
    format, then DTA will invent new output filenames, like
    "OUT00000".
      You can now force DTA to use the original filename
    even in those situations if you use the new /FO (force
    original filename) switch.
      DTA might still not pick the right filename when you're
    using multiple layers, because it'll always use the first
    filename in the first channel group in the first layer.
    If, for example, you're overlaying a signature or log over a
    bunch of input pictures, like this:
      DTA PICS*.TGA /L SIGN.TGA /FG /FO
    it'll be okay because each .GIF file will use the filename
    from the first layer (PICS*.TGA).
    But if you're overlaying a bunch of pictures onto a single
    background, like this:
      DTA BACK.TGA /L PICS*.TGA /FG /FO
    it won't be okay, because each output picture will get saved
    as BACK.GIF.  In that circumstance tell DTA to use the
    filenames from the second layer, like this:
      DTA BACK.TGA /L PICS*.TGA /FG /FO2
    You can also specify a specific channel group, like this:
      DTA /CHR X*.TGA /CHG Y*.TGA /CHB Z*.TGA /FG /FO1,2
    (the 1 means the first layer... you have to specify a
    layer when you're specifying a channel, even if there's
    only one.  The 2 means the second channel group in the
    command, green in this case.)
     You can use /FO to force DTA to replace your original
    files after processing, like this:
      DTA *.GIF /ROT90 /FG /FO
  o Added read/write support for MindImage .RLE files.
    (These are the .RLE files used for the random dot
    stereogram program MindImage... DTA can NOT read any of
    the many other file formats that also use the extention
    .RLE)
      You read one of these files just like you would any other,
    by using the filename in the command line.  For example,
    to convert a RLE to a GIF file, type:
     DTA HUMAN.RLE /FG
      To write a RLE, use the new /FR switch.  Be warned that
    MindImage expects pictures' dimensions to be powers of two
    with a maximum of 512.  So, DTA will always force pictures
    to have horizontal and vertical dimensions of 64, 128,
    256, or 512.  If a dimension is larger than 512, then
    it'll be chopped down to 512.  Otherwise, unless a dimension
    is exactly equal to one of the allowed dimensions, it'll
    be increased to match.  If the dimensions that are selected
    for you are different from the original dimensions, DTA
    will crop or extend the picture.  For example, if you start
    with a 640x480 picture, DTA will chop off a little from the
    left and right to pare the 640 down to 512, and add enough
    black border to the top and bottom to extend the 480 to 512.
    Make DTA rescale the image to the new dimensions with the /SC
    switch.  In the 640x480 example,
     DTA 640.GIF /FR /SC
    will cause the 640x480 image to be rescaled to exactly
    512x512.
     DTA 640.GIF /FR /R128,128
    will result in a 128x128 image chopped from the middle of
    the starting image.  The next two commands:
     DTA 640.GIF /FR /SC128,128
     DTA 640.GIF /FR /R128,128 /SC
    both result in a 128x128 image with the whole rescaled to
    fit exactly.
  o Added read-only support for IFF/ILBM files, 24-bit variety
    only.  Files with extensions of .IFF and .LBM will be
    recognized.
  o Changed the default 16-bit flic format from .FLX to .FLH.
    .FLX is still supported to make life easier for users of
    Mathematica's Tempra Turbo Animator (the program that first
    supported that format).  Just use the /FLX switch to tell
    DTA to use .FLX instead of .FLH.
      The basic (only?) difference between .FLX and .FLH is that
    they compress the first frame differently.  .FLX uses a
    byte-oriented scheme which does not compress 16-bit pictures
    very well.  .FLH uses a word-oriented scheme which works much
    better.
      (My DFV flic player can read either.  Tempra Turbo Animator
    will not be able to read the .FLH files.)
  o Added support for .FLT (24-bit) flics.  Just use the /B24
    switch to tell it to build a .FLT in stead of .FLC.
      At the moment, my DFV player is the only player that can
    can view this variation of the flic format... if anybody out
    there wants some info on the modifications I made to the flic
    format to support 24-bit, let me know.  They're not too
    complicated, and they're not a secret.
  o Because 24-bit flics can get so *huge*, I added some tricks
    for minimizing the size.  First, the /TO (flic tolerance)
    switch, which causes DTA to ignore pixel differences between
    frames when the distance in color-space is less than or
    equal to a value that you supply.
      I know that explanation leaves something to be desired
    ... to understand what's going on, try it out by adding
    "/TO15" at the end of a command line.  The result will
    usually be a smaller flic that plays more quickly and
    doesn't look quite as good.
      This trick works better with digitized video than it does
    with rendered animation.
      Sometimes this gimmick produces a side effect of faint
    trails on the screen when you animate anti-aliased images.
    Try the /TX switch (which isn't really an acronym of anything)
    with a number, for example "/TX5".  In that case, one frame
    in every 5 will be a full difference frame with no
    tolerance, and the trails will disappear.
      /TO and /TX work only with 24-bit flics.  I'll probably
    add it later for 8-bit and 16-bit flics.
  o Added /INV which inverts either whole colors or individual
    color channels.  You can do /INVR, /INVG, /INVB, /INVA,
    or combinations of them.  Specifying just "/INV" is the same
    as specifying "/INVR /INVG /INVB".
    If you use any /INV option with /NM (no remapping of
    mapped files) then color indexes will be inverted
    instead of color components.
  o Added /RED, /GREEN, /BLUE, and /ALPHA switches which
    let you extract a particular channel from an image.
    So, you can:
      DTA PICTURE /RED
    to create a grayscale image from just the red component, or:
      DTA X*.TGA /CHR X*.TGA /BLUE /CHB Y*.TGA /RED
    to first load in each picture as a regular 32-bit image,
    then replace the red channel with the original blue channel
    and then replace the blue channel with the red channel from
    a completely different set of pictures.
    This is fairly useless most of the time, but it should
    make some really wild effect possible.
  o Added /SCF (fast scaling).  Use it like /SC.  It works
    a *lot* faster than /SC, but looks really bad, because
    it doesn't use any interpolation.
  o Added /CLP (post-scale clipping) which works just like /CL
    but it clips the picture after scaling takes place.
    If you type:
     dta x.tga /sc500,500 /cl120,120,100,100 /pcl140,140,150,150
    DTA will read in the picture and clip out a 100x100 window
    from the picture (at coordinates 120,120), then rescale
    the clipped window to 500x500, and then clip out a 150x150
    window from the scaled picture (at coordinates 140,140).
  o Fixed a bug: DTA would ignore /332 and /G palette options
    if you were outputting to a GIF file.
  o Got rid of /ST (start) parameter, replaced it with
    /LOC.  Syntax is now /LOC#,#,# (default=0,0,0).
    The first two numbers are the x,y coords on the screen
    (from the center) where the center of the image should
    go.... Unless you specify /LL (which tells DTA to base the
    location on the left edge of the screen and image), /LR
    (right edge), /LT (top edge), or /LB (bottom edge).
    The third number is a time variable, specified as a
    percentage.
      If you specify /LOC0,0,0 that means put the image at
    0,0 at the beginning of the animation.  Add /LOC25,25,50
    and the image will be put at coords 25,25 at exactly halfway
    through the animation. If you don't specify a #,#,100,
    then DTA will assume you want the final location to loop
    back to the starting point.  You can enter as many or
    few /LOC parameters per layer as you want...
    DTA will use an interpolating spline to figure out the
    actual locations per frame.
      Unlike the old /ST, pictures can be placed at non-integer
    locations.  If you do, your picture will be resampled.
  o Added arbitrary rotation.  So you can specify /rot45
    (or /rot110.25 for that matter).
    You can add time values after multiple /ROT switches
    just like you can after /LOC.
      To get a full rotation, you could do "/ROT0,0 /ROT360,100".
    If rot[100%]-rot[0] is a multiple of 360, then the final
    rotation value will not be used ... this helps produce
    a smooth loop.
      Rotation uses smooth resampling.
  o Input pictures that are larger than the output picture
    are now centered... instead of only the top corner
    showing, the center will show.
  o Added read-only support for Type-1 TGA files (8-bit,
    colormapped).
  o Added /CC (chroma-key color), which allows you to specify
    what color DTA should replace matching pixels with.  The
    default is still 0,0,0,0 (black, fully transparent).
  o Averaging and scaling now handle 32-bit pixels correctly
    ... previously they didn't take the alpha byte into
    account properly.  As a result, colors (in areas where
    alpha-blending was taking place) would sometimes come
    out too dark or too light.
    As a result, these two functions are slower than they
    used to be... but I think the other speedups will cancel
    it out.
  o Made DTA write 8- and 24-bit PCX files (it did a couple years
    ago, but only 8-bit and then I pulled it out to save
    room.  Now that DTA's protected mode, there's no reason
    not to support this output format).
  o Made DTA read and write Vistapro .VAN animation files.
  o DTA can now write as well as read BMP files, with
    /FB switch.  /FD switch creates the same type of file,
    but uses the .DIB extension instead of .BMP
    By default, it creates 24-bit BMPs, but you can
    make it create 8-bit BMPs by adding the /B8 switch.
  o Fixed a bug in flic-reading... if a flic contained
    a partial palette (fairly rare), DTA would get confused
    and crash.
 Rel 2.0.8 (10/22/93)
  o Added 90 degree increment rotation... use "/ROT90", "/ROT180",
    "/ROT-90", "/ROT270" etc.
    Note: this is the order that operations get done...
    First rotation, next scaling, next clipping.
    So if you did "/cl100,100 /sc200,200 /rot90"
    then DTA will first rotate the picture 90 degrees to the
    right, then scale it to 200x200, and then clip off the
    top half and left half of the scaled, rotated image.
  o Expanded /R switch... in addition to preset resolution
    numbers like "/R6", you could also set the resolution
    explicitly like "/R640,480".  Just be careful that, if you're
    creating a .FLC file *don't* pick an odd number for the
    horizontal dimension: "/R149,200" is a no-no.
    (That's not a limitation of the .FLC format, just of
    my implementation.)
  o Reworked the way scripts work (you know, like "@pics.scr").
    Scripts can now include regular command-line switches
    in addition to filenames.  Just make sure that you've got
    a new file name or switch on each line of the script file.
    You can even include the name of a new script file...
    Just try to avoid recursive script files...
    *Don't* put "@script1.scr" inside of SCRIPT1.SCR, and
    *don't* put "@script1.scr" inside of SCRIPT2.SCR if SCRIPT2.SCR
    is called by SCRIPT1.SCR.
    Or DTA will go into an infinite loop and hang up.
  o If you don't include an extension with an @filename, DTA
    will add '.SCR' to the filename.
  o Fixed some clipping bugs.
  o DTA would sometimes crash with an out-of-heap-memory
    runtime error when flipping a large upside-down TGA file.
    Fixed.
 Rel 2.0.7 (09/30/93)
  o Scaling didn't work right when DTA was reading from a
    flic (probably also when reading an upside-down
    TGA and creating a GIF or TGA).
    Fixed.
 Rel 2.0.6 (09/27/93)
  o Fixed some more bugs in compositing and chroma-key.
 Rel 2.0.5 (09/12/93)
  o Finally got rid of the protection fault that invariably
    occurred after DTA finished building a .FLX file.
 Rel 2.0.4 (09/01/93)
  o Discovered a strange 'feature' in TGA files produced by
    a program called Imagine.  Even though they are unmapped
    24-bit images, for some reason they contain a color map.
    Because DTA doesn't support colormapped TGA files, I
    never paid any attention to color-map info... so DTA
    just would ungraciously treat the color-map in such files
    as if it were part of the image.
    DTA still doesn't read colormapped TGA files, but now if
    there's a color-map in an unmapped picture, it'll at
    least bypass it correctly.
 Rel 2.0.3 (08/25/93)
  o Added inverse chroma-key (/CI).  Works the same as chroma-key
    but backwards... only matching colors *won't* be made
    transparent.
  o Couldn't read .FLC files created with Autodesk Animator...
    it got confused when it ran into the optional "prefix" and
    "postage stamp" chunks.  Fixed.
  o Had problems reading 16-bit TGA files... sometimes
    resulting in page faults, sometimes in bad output.
    Fixed.
  o (There still seems to be a problem with .FLC files
     created with DTA... some players choke on some flics.
     And there's still that irritating page fault after it
     finishes building a .FLX file... I'm working on 'em.)
 Rel 2.0.2 (08/11/93)
  o Multiple layers didn't work right with /NM (no remapping)...
    only the bottom layer would show up in the final picture.
    Now it works, including chroma-key.
    Note: remember, all pictures in all layers must be colormapped,
    and must share the same palette for /NM to work right.
 Rel 2.0.1 (08/04/93)
  o Fixed a bug in /CL (clipping).
  o Fixed a bug in /CH (chroma-key).
 Rel 2.0 (07/29/93)
  o DTA can now read FLIC files.
  o DTA can now read DIB/BMP files.
  o DTA can now read Presidio .ANI files.
  o DTA can read and write hicolor Tempra ".FLX" files.
    Just specify /B16 (for 16-bit) on the command line to
    build an FLX instead of an FLI or FLC.
    (This feature seems to work well enough, but there are
    still some bugs.
    For some reason I haven't figured out yet, DTA crashes
    with a General Protection fault whenever it builds a FLX file.
    This only happens after it's finished building the animation.)
  o Now including the FLISPEED program with the DTA package.
    This'll change the speed value in the header of a flic
    without requiring you to rebuild the animation.
    Just type:
      flispeed xxx.fli /s5
    to change xxx.fli to a speed value of 5.
  o Added multi-layer (use /L to separate layers) compositing.
    Like this: DTA BACKGRND.TGA /L FORE*.TGA
    If FORE*.TGA are 32-bit TGAs with alpha, then
    DTA will make use of the transparency info.
  o Added chroma-key (use /CHr,g,b to specify a transparent
    color) ... this works okay, but not nearly as good as
    starting with 32-bit TGA files containing transparency
    info (which you can create in Polyray and, I'm told,
    3D Studio).
    You can use this feature to create 32-bit TGA files that
    contain alpha information like this: DTA *.TGA /OT /B32 /CH255,0,0
    (DMorf fans: DMorf will morph the alpha info along with the
    color info... but DMorf can add alpha better than DTA can.)
    Or, DTA BACKGRND.GIF /L FORE*.GIF /CH0,0,0 to composite a
    over a background... DTA will make all black pixels transparent.
      /CT specifies a tolerance for chroma-key.  If you (for example
    specify "/CH0,255,0 /CT5" then all pictures in the range
    <0,250,0> and <5,255,5> will become transparent.
  o Added /REP# which repeats a single frame a specified number
    of times.  Useful for inserting pauses in your flics.
    For example, if you type
      DTA before.tga /rep10 morf*.tga after.tga /rep10
    before.tga and after.tga each get repeated ten times.
    Note that this'll only create a pause if you have a speed
    value greater than 0.
  o Added /STx,y (start) ... instead of centering a picture
    on the screen, you can tell DTA where to place the top-left
    hand corner of an image on the screen.  You can have a separate
    start value for each layer.
  o Added /CLx1,y1,x2,y2 (clip)
    X1 and Y1 specify the top-left corner of the clipping window,
    and X2 and Y2 specify the size of the clipping window.
    Clipping takes place AFTER scaling, if you use both.
    You can have a separate clip for each layer.
  o Got rid of /SX (scale X) and /SY (scale Y)... just use /SCx,y
    for scaling.
    You can have a separate scale value for each layer.
  o No more real-mode executable.  DTA is just getting too darn
    big.  Maybe I'll build a pared-down DTALITE or something
    later on, if there's any demand.
  o Fiddled with the status display some.
  o Skipped 1.9... I think the amount of change justifies going
    all the way to a new major release number.  Alexander
    Enzmann requested flic-reading way back even before I
    released 1.0 and here it is, finally.
  o Probably some other stuff I've forgotten about.
  o Fixed a bunch of bugs (and probably added some new ones
    while putting in new features).
 Rel 1.8g (01/18/93)
  o Added comments to @files... just prefix comments with a ";".
  o DTA now ignores blank lines in @files.
  o Fixed assorted bugs.
  o Added grayscale TIF output (/FI)
  o Added /I option, which works like /K (skip), except instead
    of specifying how many frames to skip, specify the total
    number of frames you want in your flic.  So if you have
    50 files... X000.TGA, X001.TGA, on up to X049.TGA, and
    you type:
     dta x*.tga /i10
    then DTA will create a 10-frame flic from X000, X004, X009,
     etc.
 Rel 1.8f (12/30/92)
  o Fixed some more bugs.
  o Added support for 8-bit grayscale TGA files (type 3).
    (To create one, use /B8 /FT).
  o Added picture rescaling.  The /SC option, which only works
    when you're creating flics, rescales an image so it's the same
    size as the screen resolution.
    The /SW option rescales an image so it's the same width as the
    screen resolution (or, if you enter a number, like /SW100,
    to the width that you specify... if you use /SW for an output
    format other than a flic, then a specified width is required)
    The /SD option rescales an image so it's the same depth as the
    screen resolution (or, if you enter a number, like /SD100,
    to the depth that you specify... if you use /SD with an output
    format other than a flic, then a specified width is required)
 Rel 1.8e (12/17/92)
  o For some reason the /NM option didn't work anymore.  Fixed.
  o Fixed a bug in FLC compression... it caused the wrong pixels
    to be updated when there was a change in a pixel row after a
    run of more than 254 unchanged pixels.
  o Fixed a bug that caused a page-fault (runtime error 216)
    when creating GIF or TGA files in the protected mode
    version.
  o There used to be a limit on the width of pictures that DTA
    could process... if you made it read a picture wider than
    1280 pixels, you'd either get a spectacular crash requiring
    a reboot (real mode) or an error message (protected mode).
    Now it should be able to process pictures with a width up
    to 16K pixels or so without crashing.
 Rel 1.8d (11/30/92)
  o Fixed one bug, which prevented DTA from creating 1-frame
    flics correctly.
  o Including two versions of DTA... DTA.EXE (real mode) and
    DTAX.EXE (protected mode).  The memory management stuff
    that I included in 1.8b and 1.8c is now separated into
    another archive, DTAMEM.ZIP.
    The real-mode version runs faster than the protected-mode
    version, but only gives you access to 640K of memory.
 Rel 1.8c (11/27/92)
  o Whoops, introduced some new bugs in 1.8b.  Got ZIP, LZH, and
    ARJ working fine, but it wouldn't read pictures outside of
    archives anymore.
 Rel 1.8b (11/27/92)
  o Fixed a bug that caused a runtime error 204 whenever a frame
    couldn't be compressed and had to be stored raw.
  o Flics of resolutions other than 320x200 are now saved with the
    extension 'FLC' instead of 'FLI'... to be consistent with
    conventions established by Autodesk's Animator Pro.
  o This is the first version of DTA to be compiled in 286 protected
    mode.  This means that DTA can access up to 16MB of extended
    memory without all that messy EMS/XMS/virtual memory management.
    It also means DTA doesn't recognize EMS or page to disk any more.
    If you require EMS or virtual memory, stick with the original
    version 1.8.
    Two extra files (DPMI16BI.OVL and RTM.EXE) are distributed
    along with DTA to support protected mode.  You must keep these
    files either in the same directory as DTA, or in the DOS path.
    When DTA is run from inside a Microsoft Windows enhanced-mode
    DOS window, it'll use Windows' DPMI services instead of the
    Borland DPMI server.
  o MAYBE fixed a bug in FLC compression.
  o DTA can read pictures stored in ZIP and ARJ archives as well
    as the previously supported LZH archives ... IF you've got the
    appropriate de-archiver (PKUNZIP.EXE, ARJ.EXE, LHA.EXE) in your
    DOS path.

 Rel 1.8 (11/08/92)
  o DTA couldn't locate PCX, IMG, or GIF files in LZH archives... fixed.
  o DTA can now read 24-bit PCX files (as well as the previously
    supported 8-bit type).
  o Added some additional error-checking so DTA will stop with an error
    message if it runs out of disk space while creating output files.
    Previously it just kept on trying to write to a full disk.
  o In a previous version, made some changes in the GIF-writing
    code to speed it up and use less memory.  As a result, upside-
    down TGAs weren't getting flipped rightside-up like they're
    supposed to... fixed.
  o Removed some useless experimental options: /L, /E, /O
    If anybody ever actually found a use for any of these, let me know
    and I'll put 'em back.
  o Removed /W, since it was only added as a workaround to a bug that's
    now finally fixed.
  o Added GIF89a input. (extension blocks are IGNORED)
  o Fiddled with output-file parameters.  You now specify the output
    filename with /O, and the format with /F instead of specifying
    both with /F
  o Added /H, which lets you adjust brightness.  /HA50 increases the
    values of red, green, and blue by 50%.  /HR200 /HG-25 increases the
    value of red by 200%, and decreases green by 25%.
  o Added /C, which lets you skip frames when scanning for a palette.
    If you use /C5, then DTA will only scan 1 picture for every 5
    in your animation.
  o Added /K, which lets you skip input files when generating a
    flic.  If you use /K3, DTA will ignore 2 frames out of every 3.
    If you use both /K2 and /C2, then DTA will skip every other
    picture, and create a palette out using only 1 of every 4
    pictures.
  o Fiddled with the time blurb so it writes in minutes and seconds
    instead of milliseconds.

 Rel 1.7g (08/27/92)
  o Fixed a rarely-encountered bug in 320x200 FLI compression.
  o Reworked the documentation (actually, Dan Farmer did most all of
    this task).

 Rel 1.7f (07/19/92)
  o Fixed some weird bugs in selecting output filenames for GIF files.
  o Added /PO option, which causes DTA to create a single optimal
    palette even when it's creating GIF files.

 Rel 1.7e (07/02/92)
  o Removed all the logging code, since the memory allocation
    problems seem to be licked.
  o First attempt at creating hi-color and true-color FLIs.
    (To create a hi-color FLI, use the /b16 parameter.  The
     resulting file with have an extension of FLH.  To create
     a true-color FLI, use /b24.  The resulting file will have
     an extension of FLT.)
    So far there's no player that will display these new files,
    but Steve Enns is working on one.
  o The color-mapping speedups in the previous version resulted
    in bad color choices in some cases.  Added an extra
    step between palette selection and color-mapping that
    should improve it.
  o Added /RA parameter (auto-resolution)... tells DTA to use
    the size of the first picture to decide how big to make
    an FLI.  Note: use this parameter only with pictures with
    even horizontal dimensions.
  o When DTA used XMS to store pictures, it wasn't always clearing
    the picture buffer when it was supposed to... resulting in
    some background garbage when animating pictures smaller than
    the FLI.
  o Added /DR (random dither) parameter.  Adds/or subtracts a
    random value from each pixel.  Random values are the same
    across frames, so FLIs shouldn't explode in size like they
    sometimes do with error-diffusion dithers like Floyd-Steinberg
    and Sierra Lite.
    Specify the range of the random number by appending a number
    to the /DR parameter, like this:
     dta *.tga /dr4
    That will result in random numbers ranging from -4 to 4.
    Note: I stole the idea from Stephen Coy's IMG2GIF program.
  o Got rid of /M parameter, which affected the order of
    color-tree pruning.  It was a failed experiments in
    improving color-selection.
  o Changed /MI (max internal colors) parameter to /M
  o Changed RLE TGA output so that line boundaries aren't
    crossed within a packet... (to avoid a VPIC bug)

 Rel 1.7d (04/25/92)
  o Fixed some more memory allocation problems.
  o Speeded up color-mapping.  When dithering, there should
    be a big speed increase.  When not dithering there should
    be a lesser increase.
  o Added Sierra Lite dithering (/DS parameter).  SL dither
    another error-diffusion-type dither, somewhat quicker
    than Floyd-Steinberg.

 Rel 1.7c (04/15/92)
  o Fixed a bug in grayscale output.
  o Reduced the amount of memory required for the color tree.
  o Fixed some other memory-related problems.
  o Got rid of V (verbose), and added /LOG (which causes
    assorted memory allocation info and other boring
    debugging-type data to be written to a file called "DTA.LOG".
  o Added /MI parameter (which means "maximum internal colors").
    The octree color routine allows only 256 colors to exist
    in the tree at any time.  Whenever the number of colors
    exceeds 256, parts of the tree get truncated.
    With /MI, you can change that maximum number of colors
    to something other than 256.
    If you change it to a number larger than 256, then the palette
    will not be reduced to 256 colors until DTA is done scanning
    pictures.
    This can result in a nicer palette, but it uses more
    memory.  I've had some nice results using "/mi2048".

 Rel 1.7b (04/01/92)
  o Rel. 1.7 was missing a last-minute .FLI bug fix and
    a document update or two.

 Rel 1.7 (03/31/92)
  o Reads 256-color PCX files.
  o Reads and writes 16, 24, and 32-bit TGA files, compressed
    or uncompressed.
    The default is compressed TGA-24.  /B16 selects 16-bit,
    /B32 selects 32-bit.  /NC selects no rle compression.
    Dithering works for TGA-16 files... But if you use ordered
    dithering, DTA ignores any 'strength' value and uses a
    default (because TGA-16 color reduction is regular).
  o When scanning for a palette, it's a lot faster than before
    when reading 256-color pictures.
  o Fixed EMS bugs.  Added support for XMS.
  o Added /332 (3/3/2 palette) option
    (If you use ordered dithering, DTA ignores any supplies
    'strength' value and uses a default).
  o Added /NM (no-remapping) option.  When reading 8-bit
    colormapped files, this tells DTA to use the original
    palette that's included in the file instead of creating
    a new palette from the colors in the picture, and to skip
    re-mapping the picture to the palette.
    If you're creating an .FLI from a bunch of .GIFs or .PCXs,
    then DTA will use the palette from the first input file,
    and it will assume that all of the pictures use the same
    palette.  This will result in slightly better-looking output,
    and DTA will generate the .FLI *MUCH* faster.
    If these files do not use the same palette, then do not
    use this option.
    /NM does not work with any sort of dithering, frame-averaging,
    or anything else that requires fiddling with colors.
    If you're converting .PCX to .GIF, then the single palette
    restriction does not apply...

 Rel 1.6 (01/25/92)
  o Can write uncompressed Targa-16 files (use the /B16 switch).
  o Can read compressed and uncompressed Targa-16 files (like
    those you can produce with POLYRAY).
  o Added /M option, which causes the palette tree-reduction
    routine to prune the most popular branches instead of
    least popular.  The resulting palette should be biased
    a bit more toward detail in a picture instead of smoothly
    shaded areas.
  o Added /L option, which allows you to set the initial
    (pre-reduction, that is) color resolution for one or
    more of the color components (r,g,b) to something other
    than the default 6 bits.  It doesn't make sense to set
    it higher than 6 bits, since that's the most VGA can display.
    But you could, for example, tell DTA to use fewer bits for
    green and blue so that the reds get more representation,
    like so:
     dta *.tga /lb2 /lg3
    (that sets the blue resolution to 2 bits and the green
    resolution to 3 bits).
  o When averaging pictures, DTA used to use an equal percentage
    of each of the original pictures.  That's still the default,
    but with the /E option, you can change this.  /E lets you
    specify two numbers: (a) the amount of weight to give the
    first picture, and (b) how much to increment that weight
    for each successive picture.  So, assuming you start with
    three TGA files, if you use this command:
     dta *.tga /a5 /e2;1 /fg
    the first frame will get a weight of 2, the second will get
    3, and the third will get 4.  Which means the resulting
    GIF file will be made up 22% from the first picture, 33%
    from the second, 44% from the third.
    This can be used with /t (trail) as well as /a (average).
    The increment number can be negative... if you want
    the first picture to stand out more than the others.
    The default for the initial weight is 1.  The default
    for the increment is 0.  If you use /e without specifying
    an increment, then the increment is set to 1.
    If you don't specify either number, then both numbers are
    set to 1.
  o Fixed a bug in averaging GIF files.
  o When creating a new TGA file, DTA forgot to use the resolution
    of the input file like it does with GIF files.  Fixed.
  o Can now ignore comments in TGA files properly.
  o When creating GIF files, DTA now saves at the same
    time it performs the mapping step, instead of saving to
    a buffer and saving it at the end.
    For pictures that would require virtual memory (bigger
    than 320x200), this'll save some time.
  o Added 640x400 resolution for low-end SVGA.

 Rel 1.5f (12/13/91)
  o DTA can now read IMG files created by the Stephen Coy's
    Vivid raytracer.
  o Speeded up some input functions that were slowed down
    because of some recently added features.
  o Another probably unsuccessful attempt to fix the same bug
    that 1.5d was supposed to fix.
  o Fixed a bug in dithering (sometimes DTA wouldn't dither
    the whole picture).
  o DTA wasn't deleting a temporary file that it sometimes
    creates.  Now it does.

 Rel 1.5e (11/24/91)
  o DTA can now read GIF files as well as TGAs.  GIF87 only,
    no interlacing allowed.
  o Added a /V (verbose) command line option.  If you
    specify this, DTA will tell you exactly how many
    bytes each frame in an animation take up.
  o Added the /W option, which forces DTA to use the
    SVGA-type compression method, even if generating
    a 320x200 .FLI.
  o By the way the fix in 1.5d didn't help.  However, the
    problem is pretty rare.  Maybe next time.
 Rel 1.5d (11/18/91)
  o Hopefully fixed a bug that caused problems with Trilobyte's
    PLAY program.
 Rel 1.5c (11/11/91)
  o Attempting to support 800x600, 1024x768, and 1280x1024
    SVGA resolutions.  Note: This is completely untested.
    I haven't the foggiest idea if it works or not.
 Rel 1.5b (11/09/91)
  o Added "expansion" feature, which inserts averaged frames
    between regular frames.
  o Fixed some bugs in some weird combinations of 3d, "pingpong",
    and "trail".

 Rel 1.5 (11/05/91)
  o Ordered dithering
  o VGA "mode x" .FLI resolutions
  o fixed a bug in 320x200 delta encoding
    which would sometimes cause animations to crash
  o "averaging" and "trailing" (where individual frames are
    created by averaging the colors across multiple input
    files).  The difference between "averaging" and "trailing" is:
     If you run an "average" of 2 on 10 .TGAs, frame 1 will be
    an average of files 1 and 2, frame 2 an average of files 3
    and 4, and so on.
     If you do a "trail" of 2 on 10 .TGAs,
    then frame 1 will be an average of 1 and 2, frame 2 an average
    of files 2 and 3, frame 3 an average of files 3 and 4, and
    so on.
  o Red/blue-type 3d
  o TGA output (pretty useless unless you're also averaging
    input files or creating 3d images).  DTA does not compress
    TGAs just yet.
  o Removed .PCX output option.

 Rel 1.4 TEST 2 (10/12/91)
  o DTA can now read compressed .TGAs.
  o DTA can new create .GIFs or .PCXs.
  o Before 1.4, DTA would give up on compressing a frame if the
    compressed version required more than about 64K to store.
    This was fine for 320x200 animations, where an uncompressed
    frame only requires 64K anyway, but it left something to
    be desired for 640x480 animations, where an uncompressed
    frame takes up about 300K.
    Now, 640x480 frames will be compressed unless the compressed
    version takes up more than about 300K.
 Rel 1.3c (09/14/31) (second bug fix)
  o .MAP files were missing carriage returns between
    lines.
 Rel 1.3b (09/13/31) (bugfix release)
  o Fixed bugs from the disastrous Rel. 1.3
    (including 640x480 .FLIs)
  o Big speed increase in palette creation

 Rel 1.3 (09/03/91)
  o 640x480 .FLIs
  o Better .FLI compression.
  o In pre-1.3, the animation was stored in a temporary file,
    then at the end a new file was created with the .FLI header,
    and then the temporary file was copied onto the end of that.
    Now, only one file is used to store the animation, and the
    header gets modified at the end of the process.
  o Frame #1 is now stored in a temporary file so that it doesn't
    need to be recreated for the "ring frame".
  o Added /G32 option for creating 32-level grayscale animations
    for laptops.
  o Fixed some bugs.

 Rel 1.2 (08/06/91)
  o Added support for exit codes returned by LHA 2.13...
    If LHA returns a non-zero exit code, DTA will abort.
  o If you hit the escape key while DTA is running,
    DTA will abort as soon as it's done processing
    an input file.
  o Changed the way input files are sorted.
  o Added /p (pingpong) option.  (makes animation go in
    0-1-2-3-4-3-2-1-0 order instead of 0-1-2-3-4-0).
  o Added support for lists of files to process.
    Tell DTA that a file is a list by preceding the filename
    by an "@" character.  A list file may contain
    the names of .TGA files or .LZH files.  You can't put
    the name of another list file in a list file.
  o Will now clip .TGA files with a resolution greater than
    320x200 instead of choking on them.
  o Added /O (sort order) option.  When DTA has to sort filenames,
    like when you use a wildcards or when you just give the name
    of an .LZH file, "/O+" (the default) will tell DTA to sort
    in ascending order, "/O-" in descending order.
    This option is positional... it will only affect files
    specified AFTER the option on the DTA command line.
    You can use this more than once on a DTA command line.

 Rel 1.1 (07/15/91)
  o Can now extract .TGA files from inside of .LZH files.
    (by shelling to LHA.EXE)  Takes longer, but can save plenty
    of disk space.
  o Added /s (to specify playing speed).
  o Doesn't choke on truncated .TGA files any more.
  o Rewrote some I/O routines so scanning palettes is quicker.