Constructor Argument
- 'file' - producer a/v from file
+ 'file' - a filename specification or URL in the form:
+ [{protocol}|{format}]:{resource}[?{format-parameter}[&{format-parameter}]]
+ For example, video4linux:/dev/video1?width=320&height=240
+ Note: on the bash command line, '&' must be escaped as '\&'
+ Use 'ffmpeg -formats' to see a list of supported protocols
+ and formats.
+
+ Details
+
+ Format parameters only appear to be useful with 'video4linux' or
+ 'audio_device' formats. For 'video4linux' the parameters are
+ width, height, frame_rate, frame_rate_base, and standard (ntsc|pal).
+ For 'audio_device' the parameters are channels and sample_rate.
Initialisation Properties
Constructor Argument
- 'file' - produce a/v from file
+ 'file' - a filename specification:
+ [{mlt-service}:]{resource} | {mlt-service}
- can also be the name of a producer service that can
accept the resource specified post construction.
Needs an argument or property for multi-card address.
- ffmpeg
-
- Description
- Constructor Argument
- Initialisation Properties
- Read Only Properties
- Dependencies
- Known Bugs
-
libdv
Description
Constructor Argument
- string target
+ string target - the filename to write to, e.g. /dev/dv1394.
Initialisation Properties
- int buffer
- string rescale
+ int buffer - the number of frames to buffer, minimum 1, default 25.
+ string rescale - a rescale method, see the Filters/rescale.
+
+ Mutable Properties
+
+ int progressive - indicates whether to use progressive or field-
+ based rendering, default 0 (off).
Read Only Properties
string video_standard - "PAL" (default), "NTSC", or "WxH"
+ Initialisation Properties
+
+ int buffer - the number of frames to buffer, minimum 1, default 25.
+ string rescale - a rescale method, see the Filters/rescale.
+ - Hint: "none" works very good with SDL output.
+
Mutable Properties
double volume - audio level factor
int audio_off - if 1, disable audio output
int scale_overlay - if 1, resample video from source pixel aspect
ratio to square pixels.
+ int progressive - indicates whether to use progressive or field-
+ based rendering, default 0 (off).
Read Only Properties
Known Bugs
- NTSC handling needs tightening up - sdl:NTSC is the only valid
- constructor for NTSC playback at the moment.
+ none
westley
Constructor Argument
resource - the name of a file in which to store the XML.
- stdout is used if not supplied.
+ - stdout is default.
Initialisation Properties
// Lock the mutex now
pthread_mutex_lock( &avformat_mutex );
+
+ // If "MRL", then create AVInputFormat
+ AVInputFormat *format = NULL;
+ AVFormatParameters *params = NULL;
+ char *standard = NULL;
+ char *mrl = strchr( file, ':' );
+
+ // Only if there is not a protocol specification that avformat can handle
+ if ( mrl && !url_exist( file ) )
+ {
+ // 'file' becomes format abbreviation
+ mrl[0] = 0;
+
+ // Lookup the format
+ format = av_find_input_format( file );
+
+ // Eat the format designator
+ file = ++mrl;
+
+ if ( format )
+ {
+ // Allocate params
+ params = calloc( sizeof( AVFormatParameters ), 1 );
+
+ // These are required by video4linux (defaults)
+ params->width = 640;
+ params->height = 480;
+ params->frame_rate = 25;
+ params->frame_rate_base = 1;
+ params->device = file;
+ params->channels = 2;
+ params->sample_rate = 48000;
+ }
+
+ // Parse out params
+ mrl = strchr( file, '?' );
+ while ( mrl )
+ {
+ mrl[0] = 0;
+ char *name = strdup( ++mrl );
+ char *value = strchr( name, '=' );
+ if ( value )
+ {
+ value[0] = 0;
+ value++;
+ char *t = strchr( value, '&' );
+ if ( t )
+ t[0] = 0;
+ if ( !strcmp( name, "frame_rate" ) )
+ params->frame_rate = atoi( value );
+ else if ( !strcmp( name, "frame_rate_base" ) )
+ params->frame_rate_base = atoi( value );
+ else if ( !strcmp( name, "sample_rate" ) )
+ params->sample_rate = atoi( value );
+ else if ( !strcmp( name, "channels" ) )
+ params->channels = atoi( value );
+ else if ( !strcmp( name, "width" ) )
+ params->width = atoi( value );
+ else if ( !strcmp( name, "height" ) )
+ params->height = atoi( value );
+ else if ( !strcmp( name, "standard" ) )
+ {
+ standard = strdup( value );
+ params->standard = standard;
+ }
+ }
+ free( name );
+ mrl = strchr( mrl, '&' );
+ }
+ }
// Now attempt to open the file
- error = av_open_input_file( &context, file, NULL, 0, NULL );
+ error = av_open_input_file( &context, file, format, 0, params );
error = error < 0;
+
+ // Cleanup AVFormatParameters
+ free( standard );
+ free( params );
// If successful, then try to get additional info
if ( error == 0 )
mlt_position expected = mlt_properties_get_position( properties, "video_expected" );
// Calculate the real time code
- double real_timecode = producer_time_of_frame( this, position );
+ double real_timecode = producer_time_of_frame( this, position ) + mlt_properties_get_double( properties, "_v_pts_offset" );
// Get the video stream
AVStream *stream = context->streams[ index ];
if ( got_picture )
{
if ( pkt.pts != AV_NOPTS_VALUE && pkt.pts != 0 )
+ {
+ if ( current_time == 0 )
+ {
+ mlt_properties_set_double( properties, "_v_pts_offset", ( double )( pkt.pts / 1000000 ) );
+ real_timecode += pkt.pts / 1000000;
+ }
current_time = ( double )pkt.pts / 1000000.0;
+ }
else
current_time = real_timecode;
//fprintf( stderr, "AVFORMAT: sample aspect %f %dx%d\n", av_q2d( codec_context->sample_aspect_ratio ), codec_context->width, codec_context->height );
// Determine the fps
- source_fps = ( double )codec_context->frame_rate / codec_context->frame_rate_base;
+ source_fps = ( double )codec_context->frame_rate / ( codec_context->frame_rate_base == 0 ? 1 : codec_context->frame_rate_base );
// We'll use fps if it's available
if ( source_fps > 0 && source_fps < 30 )