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

#aspect_ratio ⇒ Object

returns numerical value for aspect ratio. eg. 1.33333 is 4x3



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

def aspect_ratio
  pix_num, pix_den = pixel_aspect_ratio
  encoded_size = encoded_pixel_dimensions
  aspect = (encoded_size[:width].to_f / encoded_size[:height].to_f) * (pix_num.to_f / pix_den.to_f)
  return :widescreen if aspect == (16.0/9.0)
  return :fullframe if aspect == (4.0/3.0)
  :other
end

#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

#track_get_audio_channel_count ⇒ Object 



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# File 'ext/track.c', line 370

static VALUE track_get_audio_channel_count(VALUE obj)
{
  AudioChannelLayout *layout = track_get_audio_channel_layout(obj);
  if (layout == NULL) return Qnil;

  UInt32 numChannels = (layout->mChannelLayoutTag == kAudioChannelLayoutTag_UseChannelDescriptions) ? layout->mNumberChannelDescriptions : AudioChannelLayoutTag_GetNumberOfChannels(layout->mChannelLayoutTag);
  
  free(layout);
  
  return INT2NUM(numChannels);
}

#track_get_audio_channel_map ⇒ Array

Returns an array n-channels in length

Array contains Hashes in the form: {:assignment => :description} where :description is a symbol representing an audio channel description.  eg. :Left, :Right, :Mono

Returns:

  • (Array) 


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# File 'ext/track.c', line 493

static VALUE track_get_audio_channel_map(VALUE obj)
{
  AudioChannelLayout *layout = track_get_audio_channel_layout(obj);
  if (layout == NULL) return Qnil;
  
  VALUE channels = Qnil;
  UInt32 numChannels, x, highLayoutTag;
  VALUE channel;
  char message[256];
  AudioChannelLayoutTag layoutTag = layout->mChannelLayoutTag;
  
  if (layoutTag == kAudioChannelLayoutTag_UseChannelDescriptions) {
    // using the descriptions
    // not implemented
    numChannels = layout->mNumberChannelDescriptions;
    channels = rb_ary_new2(numChannels);
    
    // loop through all channels, adding assignment descriptions
    AudioChannelDescription desc;
    char *trackStr;
    for (x=0; x < numChannels; x++) {
      desc = layout->mChannelDescriptions[x];
      trackStr = track_str_for_AudioChannelLabel(desc.mChannelLabel);

      if (trackStr != NULL) {
        ADD_CHANNEL(channels, channel, trackStr);

      } else {
         // unsupported audio channel labels
         ADD_CHANNEL(channels, channel, "UnsupportedByRMov");
         sprintf(message, "ChannelLabel unsupported by rmov: %d", desc.mChannelLabel);
         rb_hash_aset(channel, ID2SYM(rb_intern("message")), rb_str_new2(message));
      }
    }
    

  } else {
    numChannels = AudioChannelLayoutTag_GetNumberOfChannels(layoutTag);
    channels = rb_ary_new2(numChannels);

    if (layoutTag == kAudioChannelLayoutTag_UseChannelBitmap) {
      // use the bitmap approach
      // not implemented
      //rb_raise(eQuickTime, "Not Implemented: kAudioChannelLayoutTag_UseChannelBitmap in track_get_audio_channel_map");
      for (x=0; x < numChannels; x++) {
        ADD_CHANNEL(channels, channel, "UnsupportedByRMov");
        rb_hash_aset(channel, ID2SYM(rb_intern("message")), rb_str_new2("UseChannelBitmap unsupported by rmov"));
      }



    } else {
      // using a standard LayoutTag
      switch (layoutTag) {

        case kAudioChannelLayoutTag_Mono:
          ADD_CHANNEL(channels, channel, "Mono");
          break;
        
        case kAudioChannelLayoutTag_Stereo:
          ADD_CHANNEL(channels, channel, "Left");
          ADD_CHANNEL(channels, channel, "Right");
          break;
          
        case kAudioChannelLayoutTag_MatrixStereo :
          ADD_CHANNEL(channels, channel, "LeftTotal");
          ADD_CHANNEL(channels, channel, "RightTotal");
          break;

        default:
          // unsupported channels
          highLayoutTag = (layoutTag & 0xff0000) >> 16;
          sprintf(message, "layoutTag unsupported by rmov: (%dL << 16) | %d", highLayoutTag, numChannels);
          for (x=0; x < numChannels; x++) {
            ADD_CHANNEL(channels, channel, "UnsupportedByRMov");
            rb_hash_aset(channel, ID2SYM(rb_intern("message")), rb_str_new2(message));
          }
          //rb_raise(eQuickTime, "Unsupported ChannelLayoutTag in track_get_audio_channel_map: %d", layoutTag);
          break;
      }

    }

  }
  
  free(layout);
  
  return channels;
}

#track_codec ⇒ Object

Returns the name of the codec. Only valid for video tracks. Others return nil.



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# File 'ext/track.c', line 136

static VALUE track_codec(VALUE obj)
{
	ImageDescriptionHandle image_description = track_image_description(obj);
	
	if (image_description == NULL)
    return Qnil;

  UInt8 *codecStr = (*image_description)->name;
  
  VALUE out_str = rb_str_new( (char*)codecStr+1, (UInt8)codecStr[0] );

  DisposeHandle((Handle)image_description);

  return out_str;
}

#delete ⇒ Object

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



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# File 'ext/track.c', line 208

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 219

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

#track_display_pixel_dimensions ⇒ Object

returns hash of dimensions => width, :height => height of the encoded pixel dimensions



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# File 'ext/track.c', line 623

static VALUE track_display_pixel_dimensions(VALUE obj)
{
  OSErr osErr = noErr;
  ImageDescriptionHandle image_description = track_image_description(obj);
  if (image_description == NULL) goto bail;
  
  SInt32 width, height;
  osErr = ICMImageDescriptionGetProperty(image_description, kQTPropertyClass_ImageDescription, kICMImageDescriptionPropertyID_DisplayWidth, sizeof(width), &width, NULL);
  if (osErr != noErr) goto bail;

  osErr = ICMImageDescriptionGetProperty(image_description, kQTPropertyClass_ImageDescription, kICMImageDescriptionPropertyID_DisplayHeight, sizeof(height), &height, NULL);
  if (osErr != noErr) goto bail;

  VALUE size_hash = rb_hash_new();

  rb_hash_aset(size_hash, ID2SYM(rb_intern("width")), INT2NUM(width));
  rb_hash_aset(size_hash, ID2SYM(rb_intern("height")), INT2NUM(height));

  DisposeHandle((Handle)image_description);
  return size_hash;

  bail:
    DisposeHandle((Handle)image_description);
    rb_raise(eQuickTime, "Error %d when getting track_display_pixel_dimensions", osErr);
    return Qnil;
}

#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 230

static VALUE track_enable(VALUE obj, VALUE boolean)
{
  SetTrackEnabled(TRACK(obj), TRUE);
  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 241

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

#track_encoded_pixel_dimensions ⇒ Object

returns hash of dimensions => width, :height => height of the encoded pixel dimensions



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# File 'ext/track.c', line 589

static VALUE track_encoded_pixel_dimensions(VALUE obj)
{
  OSErr osErr = noErr;
  ImageDescriptionHandle image_description = track_image_description(obj);
  if (image_description == NULL) goto bail;
  
  SInt32 width, height;
  osErr = ICMImageDescriptionGetProperty(image_description, kQTPropertyClass_ImageDescription, kICMImageDescriptionPropertyID_EncodedWidth, sizeof(width), &width, NULL);
  if (osErr != noErr) goto bail;

  osErr = ICMImageDescriptionGetProperty(image_description, kQTPropertyClass_ImageDescription, kICMImageDescriptionPropertyID_EncodedHeight, sizeof(height), &height, NULL);
  if (osErr != noErr) goto bail;

  VALUE size_hash = rb_hash_new();

  rb_hash_aset(size_hash, ID2SYM(rb_intern("width")), INT2NUM(width));
  rb_hash_aset(size_hash, ID2SYM(rb_intern("height")), INT2NUM(height));

  DisposeHandle((Handle)image_description);
  return size_hash;

  bail:
    DisposeHandle((Handle)image_description);
    rb_raise(eQuickTime, "Error %d when getting track_encoded_pixel_dimensions", osErr);
    return Qnil;
}

#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

#track_height ⇒ Object

Returns the height of track data. Only valid for video tracks. Others return nil.



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

static VALUE track_height(VALUE obj)
{
	ImageDescriptionHandle image_description = track_image_description(obj);
	
	if (image_description == NULL)
    return Qnil;

  short height = (*image_description)->height;
  
  DisposeHandle((Handle)image_description);

  return INT2NUM(height);
}

#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 198

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 86

static VALUE track_media_type(VALUE obj)
{
  OSType media_type = track_get_media_type(obj);
  
  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 314

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 328

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 300

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 276

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 286

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

#track_pixel_aspect_ratio ⇒ 1

Returns ].

Returns:

  • (1) —

    ]



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# File 'ext/track.c', line 655

static VALUE track_pixel_aspect_ratio(VALUE obj)
{
  OSErr osErr = noErr;
  ImageDescriptionHandle image_description = track_image_description(obj);
  if (image_description == NULL) goto bail;
  
  PixelAspectRatioImageDescriptionExtension dimension;
  osErr = ICMImageDescriptionGetProperty(image_description, kQTPropertyClass_ImageDescription, kICMImageDescriptionPropertyID_PixelAspectRatio, sizeof(dimension), &dimension, NULL);
  if (osErr != noErr) goto bail;
  
//  printf("\naspect ratio: %d:%d\n", dimension.hSpacing, dimension.vSpacing);
  VALUE aspect_ratio = rb_ary_new3(2, INT2NUM(dimension.hSpacing), INT2NUM(dimension.vSpacing));

  DisposeHandle((Handle)image_description);
  return aspect_ratio;

  bail:
    DisposeHandle((Handle)image_description);
    rb_raise(eQuickTime, "Error %d when getting track_encoded_pixel_dimensions", osErr);
    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)));
}

#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)));
}

#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 255

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 265

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

#track_width ⇒ Object

Returns the width of track data. Only valid for video tracks. Others return nil.



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# File 'ext/track.c', line 158

static VALUE track_width(VALUE obj)
{
	ImageDescriptionHandle image_description = track_image_description(obj);
	
	if (image_description == NULL)
    return Qnil;

  short width = (*image_description)->width;
  
  DisposeHandle((Handle)image_description);

  return INT2NUM(width);
}