Class: QuickTime::Track

Inherits:
Object
  • Object
show all
Defined in:
lib/quicktime/track.rb,
ext/track.c

Overview

see ext/track.c for additional methods

Instance Method Summary collapse

Instance Method Details

#audio? ⇒ Boolean

Returns true/false depending on if track is an audio track.

Returns:

  • (Boolean) 


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# File 'lib/quicktime/track.rb', line 16

def audio?
  media_type == :audio
end

#bounds ⇒ Object

Returns a hash of boundaries. The hash contains four keys: :left, :top, :right, :bottom. Each holds an integer representing the pixel value.



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# File 'ext/track.c', line 301

static VALUE track_bounds(VALUE obj)
{
  VALUE bounds_hash = rb_hash_new();
  RgnHandle region;
  Rect bounds;
  region = GetTrackDisplayBoundsRgn(TRACK(obj));
  GetRegionBounds(region, &bounds);
  DisposeRgn(region);
  rb_hash_aset(bounds_hash, ID2SYM(rb_intern("left")), INT2NUM(bounds.left));
  rb_hash_aset(bounds_hash, ID2SYM(rb_intern("top")), INT2NUM(bounds.top));
  rb_hash_aset(bounds_hash, ID2SYM(rb_intern("right")), INT2NUM(bounds.right));
  rb_hash_aset(bounds_hash, ID2SYM(rb_intern("bottom")), INT2NUM(bounds.bottom));
  return bounds_hash;
}

#delete ⇒ Object

Removes the track from its movie and deletes it from memory.



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# File 'ext/track.c', line 109

static VALUE track_delete(VALUE obj)
{
  DisposeMovieTrack(TRACK(obj));
  return Qnil;
}

#disable ⇒ Object

Disables the track. See enabled? to determine if it’s disabled already.



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# File 'ext/track.c', line 120

static VALUE track_disable(VALUE obj, VALUE boolean)
{
  SetTrackEnabled(TRACK(obj), FALSE);
  return obj;
}

#duration ⇒ Object

Returns the length of this track in seconds using raw_duration and time_scale.



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# File 'lib/quicktime/track.rb', line 6

def duration
  raw_duration.to_f/time_scale
end

#enable ⇒ Object

Enables the track. See enabled? to determine if it’s enabled already.



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# File 'ext/track.c', line 131

static VALUE track_enable(VALUE obj, VALUE boolean)
{
  SetTrackEnabled(TRACK(obj), TRUE);
  return obj;
}

#enable_alpha ⇒ Object

Enable the straight alpha graphic mode for this track.

This is best used on an overlayed video track which includes some alpha transparency (such as in a PNG image).



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# File 'ext/track.c', line 243

static VALUE track_enable_alpha(VALUE obj)
{
  MediaSetGraphicsMode(GetMediaHandler(TRACK_MEDIA(obj)), graphicsModeStraightAlpha, 0);
  return obj;
}

#enabled? ⇒ Boolean

Returns true/false depending on if the track is enabled.

Returns:

  • (Boolean) 


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# File 'ext/track.c', line 142

static VALUE track_enabled(VALUE obj, VALUE boolean)
{
  if (GetTrackEnabled(TRACK(obj)) == TRUE) {
    return Qtrue;
  } else {
    return Qfalse;
  }
}

#frame_count ⇒ Object

Returns the number of frames in the track.



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# File 'ext/track.c', line 67

static VALUE track_frame_count(VALUE obj)
{
  return INT2NUM(GetMediaSampleCount(TRACK_MEDIA(obj)));
}

#frame_rate ⇒ Object

The average frame_rate for this track. May not be exact.



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# File 'lib/quicktime/track.rb', line 11

def frame_rate # what about odd frame rates such as 29.97?
  frame_count/duration
end

#height ⇒ Object

Returns the bounding height of this track in number of pixels.



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# File 'lib/quicktime/track.rb', line 36

def height
  bounds[:bottom] - bounds[:top]
end

#id ⇒ Object

Returns either id number QuickTime uses to reference this track. Usually only used internally.



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# File 'ext/track.c', line 99

static VALUE track_id(VALUE obj)
{
  return INT2NUM(GetTrackID(TRACK(obj)));
}

#load(movie, index) ⇒ Object

Loads a QuickTime track from a given movie. This is done automatically when calling movie.tracks.



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# File 'ext/track.c', line 31

static VALUE track_load(VALUE obj, VALUE movie_obj, VALUE index_obj)
{
  RTRACK(obj)->track = GetMovieIndTrack(MOVIE(movie_obj), NUM2INT(index_obj));
  if (!RTRACK(obj)->track)
    rb_raise(eQuickTime, "Unable to fetch track for movie at index %d", NUM2INT(index_obj));
  
  return obj;
}

#media_type ⇒ Object

Returns either :audio or :video depending on the type of track this is.



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# File 'ext/track.c', line 77

static VALUE track_media_type(VALUE obj)
{
  OSType media_type;
  
  GetMediaHandlerDescription(TRACK_MEDIA(obj), &media_type, 0, 0);
  if (media_type == SoundMediaType) {
    return ID2SYM(rb_intern("audio"));
  } else if (media_type == VideoMediaType) {
    return ID2SYM(rb_intern("video"));
  } else if (media_type == TextMediaType) {
    return ID2SYM(rb_intern("text"));
  } else {
    return Qnil;
  }
}

#new_audio_media ⇒ Object

Creates a new audio media for this track.

Generally this method is not called directly, instead you can make a new audio track using Movie#new_audio_track.



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# File 'ext/track.c', line 215

static VALUE track_new_audio_media(VALUE obj)
{
  NewTrackMedia(TRACK(obj), SoundMediaType, 44100, 0, 0);
  return obj;
}

#new_text_media ⇒ Object

Creates a new text media for this track.

Generally this method is not called directly, instead you can make a new text track using Movie#new_text_track.



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# File 'ext/track.c', line 229

static VALUE track_new_text_media(VALUE obj)
{
  NewTrackMedia(TRACK(obj), TextMediaType, 600, 0, 0);
  return obj;
}

#new_video_media ⇒ Object

Creates a new video media for this track.

Generally this method is not called directly, instead you can make a new video track using Movie#new_video_track.



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# File 'ext/track.c', line 201

static VALUE track_new_video_media(VALUE obj)
{
  NewTrackMedia(TRACK(obj), VideoMediaType, 600, 0, 0);
  return obj;
}

#offset ⇒ Object

Returns the offset of the track from the beginning of the movie (in seconds).



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# File 'ext/track.c', line 177

static VALUE track_get_offset(VALUE obj)
{
  return rb_float_new((double)GetTrackOffset(TRACK(obj))/GetMediaTimeScale(TRACK_MEDIA(obj)));
}

#offset=(seconds) ⇒ Object

Sets the offset of the track from the start of the movie (in seconds).



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# File 'ext/track.c', line 187

static VALUE track_set_offset(VALUE obj, VALUE seconds)
{
  SetTrackOffset(TRACK(obj), TRACK_TIME(obj, seconds));
  return Qnil;
}

#raw_duration ⇒ Object

Returns the raw duration of the track. Combine this with time_scale to reach the duration in seconds.



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# File 'ext/track.c', line 46

static VALUE track_raw_duration(VALUE obj)
{
  return INT2NUM(GetMediaDuration(TRACK_MEDIA(obj)));
}

#reset_transformations ⇒ Object

Revert any transformations (scale, translate, rotate) performed on this track.



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# File 'ext/track.c', line 321

static VALUE track_reset_transformations(VALUE obj)
{
  MatrixRecord matrix;
  GetTrackMatrix(TRACK(obj), &matrix);
  SetIdentityMatrix(&matrix);
  SetTrackMatrix(TRACK(obj), &matrix);
  return obj;
}

#rotate(degrees) ⇒ Object

Rotate the track by the given number of degrees.



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# File 'ext/track.c', line 286

static VALUE track_rotate(VALUE obj, VALUE degrees)
{
  MatrixRecord matrix;
  GetTrackMatrix(TRACK(obj), &matrix);
  RotateMatrix(&matrix, FloatToFixed(NUM2DBL(degrees)), 0, 0);
  SetTrackMatrix(TRACK(obj), &matrix);
  return obj;
}

#scale(width, height) ⇒ Object

Scale the track’s size by width and height respectively.

The value passed is a relative float where “1” is the current size.



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# File 'ext/track.c', line 256

static VALUE track_scale(VALUE obj, VALUE width, VALUE height)
{
  MatrixRecord matrix;
  GetTrackMatrix(TRACK(obj), &matrix);
  ScaleMatrix(&matrix, FloatToFixed(NUM2DBL(width)), FloatToFixed(NUM2DBL(height)), 0, 0);
  SetTrackMatrix(TRACK(obj), &matrix);
  return obj;
}

#text? ⇒ Boolean

Returns true/false depending on if track is a text track.

Returns:

  • (Boolean) 


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# File 'lib/quicktime/track.rb', line 26

def text?
  media_type == :text
end

#time_scale ⇒ Object

Returns the time scale of the track. Usually only needed when working with raw_duration.



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# File 'ext/track.c', line 57

static VALUE track_time_scale(VALUE obj)
{
  return INT2NUM(GetMediaTimeScale(TRACK_MEDIA(obj)));
}

#translate(x, y) ⇒ Object

Offset a track’s position by x and y values respectively.

Values should be in pixels.



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# File 'ext/track.c', line 272

static VALUE track_translate(VALUE obj, VALUE x, VALUE y)
{
  MatrixRecord matrix;
  GetTrackMatrix(TRACK(obj), &matrix);
  TranslateMatrix(&matrix, FloatToFixed(NUM2DBL(x)), FloatToFixed(NUM2DBL(y)));
  SetTrackMatrix(TRACK(obj), &matrix);
  return obj;
}

#video? ⇒ Boolean

Returns true/false depending on if track is a video track.

Returns:

  • (Boolean) 


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# File 'lib/quicktime/track.rb', line 21

def video?
  media_type == :video
end

#volume ⇒ Object

Returns the volume of the audio from 0.0 to 1.0.



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# File 'ext/track.c', line 156

static VALUE track_get_volume(VALUE obj)
{
  return rb_float_new((double)GetTrackVolume(TRACK(obj))/0x0100);
}

#volume=(volume_float) ⇒ Object

Sets the volume to the given value (0.0 to 1.0)



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# File 'ext/track.c', line 166

static VALUE track_set_volume(VALUE obj, VALUE volume_obj)
{
  SetTrackVolume(TRACK(obj), (short)(0x0100*NUM2DBL(volume_obj)));
  return Qnil;
}

#width ⇒ Object

Returns the bounding width of this track in number of pixels.



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# File 'lib/quicktime/track.rb', line 31

def width
  bounds[:right] - bounds[:left]
end