1. Exposed Interfaces
    1. IAMMediaContent
    2. IAMOpenProgress
    3. ISupportedSites
    4. IPropertyBag, IPropertyBag2
  2. Settings Overriding


Exposed Interfaces

Among with interfaces that are usual for DirectShow source filter (IBaseFilter, IFileSourceFilter, IAMFilterMiscFlags, ISpecifyPropertyPages), filter exposes few other standard and custom interfaces. They are listed below. Not all methods of these interfaces are implemented. Unimplemented ones return E_NOIMPL.


Implemented methods:

Returned text is ready to use, i.e. there are no URL encoding, HTML entities or tags.


Unsupported since version 2.0.


Implemented methods:

  • get_BufferingProgress Filter uses it to report total downloading progress of all media streams. When option Downloading the clip is turned off (and thus no such info can be provided) or option Enable buffering notification is turned off, it will return S_FALSE and zero progress.


Implemented methods:



This interface provides info about supported sites and exposes the way to test whether particular URL is supported or not.

This is custom interface, detailed description can be found in the archive below.


IPropertyBag, IPropertyBag2


Using these interfaces filter exposes additional metadata.

List of exposed fields:

titleOriginal video title on the site
descriptionVideo description on the site
channel_titleThe title of the channel to which belongs the video. In most cases this is display name of the user but not always: channels on Youtube may not be associated with a user. Also in case of Youtube this is a display name of the channel. I.e. it does not have to be unique so different channels can have the same display name
channel_urlURL of the channel containing this video. Unlike channel_title, this URL is unique for each channel
upload_dateUpload date in format YYYY-MM-DD
view_countNumber of times that the video has been viewed
thumbnail_urlURL to the video thumbnail
like_count, dislike_countNumber of people who liked/disliked the video

Note, since version 2.0 field dwHint field of PROPBAG2 structure is unused.

Settings Overriding

Unsupported since version 2.0.


All quality-related settings and few other settings can be overridden. This can be done either by custom URL parameters or programmatically via IPropertyBag/IPropertyBag2 interfaces. The latter is available starting from version 1.8.2. If some parameter is presented using both ways, URL parameter takes precedence.

Value of URL parameter can be URL-encoded if need. Example of custom URL parameter (select 720p video):


The same with IPropertyBag:

if (CComQIPtr<IPropertyBag> bag = filter) {
  CComVariant value("720p");
  bag->Write(L"ys_video_resolution", &value);

When using IPropertyBag/IPropertyBag2, configuration should be done before calling IFileSourceFilter::Load(). All values (including numeric ones) should be passed as strings.

All parameters reflect appropriate options in filter properties, no more, no less. All overridden options that was found are be reported in Log (tab in the filter properties).

Below is complete list of parameters with mapping to appropriate option. If not stated explicitly, expected value is the same as in appropriate option from the filter properties. For check boxes expected values are 0 and 1 (unchecked and checked respectively).

URL paramMapped optionValue
ys_show_in_systrayShow icon in system tray
ys_show_err_wnd(v1.8+) Show error window when failed to open a clip
ys_video_resolutionPreferred video resolutionsmallest / 144p / 240p / 360p / 480p / 720p / 1080p / 1440p / 2160p / 3072p / best
ys_audio_bitratePreferred audio bitrateauto / 32k / 64k / 128k / 192k / 256k / best
ys_prefer_hfr(v1.7+) Prefer high frame rate videos
ys_prefer_hdr(v1.7+) Prefer high dynamic range videos
ys_prefer_3dPrefer 3D videos
ys_subs_downloadDownload subtitlesRead note below
ys_manual_selectManual quality selectionnever / always / hold_shift / hold_alt / hold_ctrl
ys_ignore_formatsFormats to ignore
ys_formats_priorityPriority of formats
ys_format_over_qualityFormat takes precedence over quality
ys_enable_dashEnable Youtube DASH streams
ys_muxing_exceptionsMuxing exceptions
ys_audio_onlyAudio-only output
ys_max_width(v1.7+) Maximum width of the video
ys_analysis_strategyGetting info about clipfast / medium / precise
ys_analysis_limitLimit of the part size
ys_predownloadDownloading the clip
ys_notify_bufferingEnable buffering notification
ys_tmpdir_typeTemporary directory (type)wintemp / custom
ys_tmpdir_pathTemporary directory (path)full path to the directory if ys_tmpdir_type=custom

Download subtitles

Prior to version 1.6 i.e. prior to auto-translated subtitles support and precise subtitles selection it had three possible values: never, all, except_asr. There all means regular subtitles + ASR and except_asr means only regular subtitles. In version 1.6 these values are still acceptable for back compatibility with exactly the same meaning i.e. auto-translated subtitles are not included in results.

Since 1.6 using this parameter can be specified any set of subtitles using next form:


where subX has format type_num=lang_tag.

Value of type_numMeaning
0Regular subtitles

Values of lang_tag are: special word _all (match any subtitle of given type) or language code (ISO 639-1 or 639-2, lowercase) appended by optional script code (ISO 15924, first letter uppercase, the rest lowercase) and/or optional country code (ISO 3166-1 alpha-2 (uppercase) or numeric). Subtitle becomes selected if its language tag contains any of provided language tags. 'Contains' means substring match, case-sensitive i.e. using generic C function it would be NULL != strstr(original_lang_tag, param_lang_tag).

For example, to download all regular subtitles, never download ASR, download English and Chinese (Traditional) auto-translated subtitles this parameter would be: