## 2. Regular Expressions The parser defines a large number of `Pattern` objects, which are compiled regular expressions. These patterns are used to extract information from the M3U8 playlist. Here is a comprehensive list of the regular expressions used by the parser: | Obfuscated Name | Regular Expression | Description | | --------------- | ----------------------------------- | --------------------------------------------------------------------------- | -------------------------------------------------------------------------------- | -------------------------------------------------------------------- | -------------------------------------------------------- | --- | ------------------------------------------------------- | | `f5286` | `#EXT-X-DATERANGE:(\d+)\b` | Parses the `END-DATE` attribute from the `#EXT-X-DATERANGE` tag. | | `f5287` | `KEYFORMAT="((?:. | \f)+?)"` | Parses the `KEYFORMAT` attribute from the `#EXT-X-KEY` tag. | | `f5288` | `VALUE="((?:. | \f)+?)"` | Parses the `VALUE` attribute. | | `f5289` | `TIME-OFFSET=(-?[\d\.]+)\b` | Parses the `TIME-OFFSET` attribute from the `#EXT-X-START` tag. | | `f5290` | `#EXT-X-VERSION:(\d+)\b` | Parses the HLS version from the `#EXT-X-VERSION` tag. | | `f5291` | `INSTREAM-ID="((?:CC | SERVICE)\d+)"` | Parses the `INSTREAM-ID` attribute from the `#EXT-X-MEDIA` tag. | | `f5292` | `X-RESTRICT="((?:. | \f)+?)"` | Parses the `X-RESTRICT` attribute. | | `f5293` | `AVERAGE-BANDWIDTH=(\d+)\b` | Parses the `AVERAGE-BANDWIDTH` attribute from the `#EXT-X-STREAM-INF` tag. | | `f5294` | `X-PLAYOUT-LIMIT=([\d\.]+)\b` | Parses the `X-PLAYOUT-LIMIT` attribute. | | `f5295` | `TYPE=(PART | MAP)` | Parses the `TYPE` attribute from the `#EXT-X-PRELOAD-HINT` tag. | | `f5296` | `FORCED=(NO | YES)` | Parses the `FORCED` attribute. | | `f5297` | `GROUP-ID="((?:. | \f)+?)"` | Parses the `GROUP-ID` attribute from the `#EXT-X-MEDIA` tag. | | `f5298` | `INDEPENDENT=(NO | YES)` | Parses the `INDEPENDENT` attribute. | | `f5299` | `PART-HOLD-BACK=([\d\.]+)\b` | Parses the `PART-HOLD-BACK` attribute from the `#EXT-X-SERVER-CONTROL` tag. | | `f5300` | `CLASS="((?:. | \f)+?)"` | Parses the `CLASS` attribute from the `#EXT-X-DATERANGE` tag. | | `f5301` | `CAN-BLOCK-RELOAD=(NO | YES)` | Parses the `CAN-BLOCK-RELOAD` attribute from the `#EXT-X-SERVER-CONTROL` tag. | | `f5302` | `RESOLUTION=(\d+x\d+)` | Parses the `RESOLUTION` attribute from the `#EXT-X-STREAM-INF` tag. | | `f5303` | `#EXT-X-TARGETDURATION:(\d+)\b` | Parses the target duration from the `#EXT-X-TARGETDURATION` tag. | | `f5304` | `BYTERANGE-START=(\d+)\b` | Parses the `BYTERANGE-START` attribute. | | `f5305` | `X-TIMELINE-STYLE="((?:. | \f)+?)"` | Parses the `X-TIMELINE-STYLE` attribute. | | `f5306` | `VIDEO="((?:. | \f)+?)"` | Parses the `VIDEO` attribute from the `#EXT-X-STREAM-INF` tag. | | `f5307` | `CAN-SKIP-DATERANGES=(NO | YES)` | Parses the `CAN-SKIP-DATERANGES` attribute from the `#EXT-X-SERVER-CONTROL` tag. | | `f5308` | `[: | ,]HOLD-BACK=([\d\.]+)\b` | Parses the `HOLD-BACK` attribute from the `#EXT-X-SERVER-CONTROL` tag. | | `f5309` | `[^-]BANDWIDTH=(\d+)\b` | Parses the `BANDWIDTH` attribute from the `#EXT-X-STREAM-INF` tag. | | `f5310` | `SUBTITLES="((?:. | \f)+?)"` | Parses the `SUBTITLES` attribute from the `#EXT-X-STREAM-INF` tag. | | `f5311` | `PART-TARGET=([\d\.]+)\b` | Parses the `PART-TARGET` attribute from the `#EXT-X-PART-INF` tag. | | `f5312` | `#EXT-X-BYTERANGE:(\d+(?:@\d+)?)\b` | Parses the byte range from the `#EXT-X-BYTERANGE` tag. | | `f5313` | `X-SNAP="((?:. | \f)+?)"` | Parses the `X-SNAP` attribute. | | `f5314` | `[:,]DURATION=([\d\.]+)\b` | Parses the `DURATION` attribute from the `#EXT-X-DATERANGE` tag. | | `f5315` | `\{\$([a-zA-Z0-9\-_]+)\} ` | Parses a variable substitution. | | `f5316` | `AUTOSELECT=(NO | YES)` | Parses the `AUTOSELECT` attribute. | | `f5317` | `LAST-MSN=(\d+)\b` | Parses the `LAST-MSN` attribute from the `#EXT-X-RENDITION-REPORT` tag. | | `f5318` | `CHARACTERISTICS="((?:. | \f)+?)"` | Parses the `CHARACTERISTICS` attribute from the `#EXT-X-MEDIA` tag. | | `f5319` | `KEYFORMATVERSIONS="((?:. | \f)+?)"` | Parses the `KEYFORMATVERSIONS` attribute from the `#EXT-X-KEY` tag. | | `f5320` | `\b(X-[A-Z0-9-]+)=` | Parses a custom `X-` attribute. | | `f5321` | `DURATION=([\d\.]+)\b` | Parses the `DURATION` attribute. | | `f5322` | `NAME="((?:. | \f)+?)"` | Parses the `NAME` attribute. | | `f5323` | `X-CONTENT-MAY-VARY="((?:. | \f)+?)"` | Parses the `X-CONTENT-MAY-VARY` attribute. | | `f5324` | `DEFAULT=(NO | YES)` | Parses the `DEFAULT` attribute. | | `f5325` | `IMPORT="((?:. | \f)+?)"` | Parses the `IMPORT` attribute from the `#EXT-X-DEFINE` tag. | | `f5326` | `#EXT-X-PLAYLIST-TYPE:(.+)\b` | Parses the playlist type from the `#EXT-X-PLAYLIST-TYPE` tag. | | `f5327` | `TYPE=(AUDIO | VIDEO | SUBTITLES | CLOSED-CAPTIONS)` | Parses the `TYPE` attribute from the `#EXT-X-MEDIA` tag. | | `f5328` | `END-ON-NEXT=(NO | YES)` | Parses the `END-ON-NEXT` attribute from the `#EXT-X-DATERANGE` tag. | | `f5329` | `BYTERANGE="(\d+(?:@\d+)?)\b"` | Parses the `BYTERANGE` attribute. | | `f5330` | `VIDEO-RANGE=(SDR | PQ | HLG)` | Parses the `VIDEO-RANGE` attribute from the `#EXT-X-STREAM-INF` tag. | | `f5331` | `X-ASSET-URI="((?:. | \f)+?)"` | Parses the `X-ASSET-URI` attribute. | | `f5332` | `CLOSED-CAPTIONS="((?:. | \f)+?)"` | Parses the `CLOSED-CAPTIONS` attribute from the `#EXT-X-STREAM-INF` tag. | | `f5333` | `URI="((?:. | \f)+?)"` | Parses the `URI` attribute from the `#EXT-X-KEY` and `#EXT-X-MAP` tags. | | `f5334` | `PRECISE=(NO | YES)` | Parses the `PRECISE` attribute from the `#EXT-X-START` tag. | | `f5335` | `#EXTINF:[\d\.]+\b,(.+)` | Parses the title of a media segment. | | `f5336` | `LANGUAGE="((?:. | \f)+?)"` | Parses the `LANGUAGE` attribute from the `#EXT-X-MEDIA` tag. | | `f5337` | `#EXTINF:\s*([\d\.]+)\b` | Parses the duration of a media segment. | | `f5338` | `LAST-PART=(\d+)\b` | Parses the `LAST-PART` attribute from the `#EXT-X-RENDITION-REPORT` tag. | | `f5339` | `SKIPPED-SEGMENTS=(\d+)\b` | Parses the `SKIPPED-SEGMENTS` attribute from the `#EXT-X-SKIP` tag. | | `f5340` | `AUDIO="((?:. | \f)+?)"` | Parses the `AUDIO` attribute from the `#EXT-X-STREAM-INF` tag. | | `f5341` | `IV=([^,.*]+)` | Parses the `IV` attribute from the `#EXT-X-KEY` tag. | | `f5342` | `[:,]ID="((?:. | \f)+?)"` | Parses the `ID` attribute from the `#EXT-X-DATERANGE` tag. | | `f5343` | `CODECS="((?:. | \f)+?)"` | Parses the `CODECS` attribute from the `#EXT-X-STREAM-INF` tag. | | `f5344` | `#EXT-X-MEDIA-SEQUENCE:(\d+)\b` | Parses the media sequence number from the `#EXT-X-MEDIA-SEQUENCE` tag. | | `f5345` | `CHANNELS="((?:. | \f)+?)"` | Parses the `CHANNELS` attribute from the `#EXT-X-MEDIA` tag. | | `f5346` | `SUPPLEMENTAL-CODECS="((?:. | \f)+?)"` | Parses the `SUPPLEMENTAL-CODECS` attribute from the `#EXT-X-STREAM-INF` tag. | | `f5347` | `FRAME-RATE=([\d\.]+)\b` | Parses the `FRAME-RATE` attribute from the `#EXT-X-STREAM-INF` tag. | | `f5348` | `GAP=(NO | YES)` | Parses the `GAP` attribute. | | `f5349` | `CUE="((?:. | \f)+?)"` | Parses the `CUE` attribute. | | `f5350` | `X-ASSET-LIST="((?:. | \f)+?)"` | Parses the `X-ASSET-LIST` attribute. | | `f5351` | `CAN-SKIP-UNTIL=([\d\.]+)\b` | Parses the `CAN-SKIP-UNTIL` attribute from the `#EXT-X-SERVER-CONTROL` tag. | | `f5352` | `START-DATE="((?:. | \f)+?)"` | Parses the `START-DATE` attribute from the `#EXT-X-DATERANGE` tag. | | `f5353` | `METHOD=(NONE | AES-128 | SAMPLE-AES | SAMPLE-AES-CENC | SAMPLE-AES-CTR)\s\*(?:, | $)` | Parses the encryption method from the `#EXT-X-KEY` tag. | | `f5354` | `PLANNED-DURATION=([\d\.]+)\b` | Parses the `PLANNED-DURATION` attribute from the `#EXT-X-DATERANGE` tag. | | `f5355` | `X-RESUME-OFFSET=(-?[\d\.]+)\b` | Parses the `X-RESUME-OFFSET` attribute. | | `f5356` | `BYTERANGE-LENGTH=(\d+)\b` | Parses the `BYTERANGE-LENGTH` attribute. | | `f5357` | `X-TIMELINE-OCCUPIES="((?:. | \f)+?)"` | Parses the `X-TIMELINE-OCCUPIES` attribute. | ## 4. Supported HLS Tags and Attributes The parser supports a wide range of HLS tags and their attributes. Here is a detailed breakdown: ### Media Segment Tags - **`#EXTINF`**: Specifies the duration and title of a media segment. - **Duration:** A floating-point number indicating the duration of the segment in seconds. - **Title:** A string representing the title of the segment. - **`#EXT-X-BYTERANGE`**: Indicates that the media segment is a sub-range of the resource identified by its URI. - **Length:** The length of the sub-range in bytes. - **Offset:** The offset from the beginning of the resource. - **`#EXT-X-DISCONTINUITY`**: Indicates a discontinuity between the media segment that follows it and the one that preceded it. - **`#EXT-X-KEY`**: Specifies how to decrypt media segments. - **`METHOD`**: The encryption method. Can be `NONE`, `AES-128`, `SAMPLE-AES`, `SAMPLE-AES-CENC`, or `SAMPLE-AES-CTR`. - **`URI`**: The URI of the key file. - **`IV`**: The initialization vector. - **`KEYFORMAT`**: The format of the key. - **`KEYFORMATVERSIONS`**: The versions of the key format. - **`#EXT-X-MAP`**: Specifies how to obtain the Media Initialization Section. - **`URI`**: The URI of the resource containing the Media Initialization Section. - **`BYTERANGE`**: The byte range of the Media Initialization Section. ### Media Playlist Tags - **`#EXT-X-TARGETDURATION`**: Specifies the maximum media segment duration. - **`#EXT-X-MEDIA-SEQUENCE`**: Indicates the sequence number of the first media segment that appears in a playlist file. - **`#EXT-X-DISCONTINUITY-SEQUENCE`**: Allows for synchronization between different renditions of the same variant stream. - **`#EXT-X-ENDLIST`**: Indicates that no more media segments will be added to the playlist file. - **`#EXT-X-PLAYLIST-TYPE`**: Provides mutability information about the playlist file. Can be `VOD` (static) or `EVENT` (dynamic). - **`#EXT-X-I-FRAMES-ONLY`**: Indicates that each media segment in the playlist describes a single I-frame. ### Master Playlist Tags - **`#EXT-X-STREAM-INF`**: Specifies a variant stream. - **`BANDWIDTH`**: The peak bandwidth of the stream. - **`AVERAGE-BANDWIDTH`**: The average bandwidth of the stream. - **`CODECS`**: A string containing a comma-separated list of the codecs used in the stream. - **`RESOLUTION`**: The resolution of the video in the stream. - **`FRAME-RATE`**: The frame rate of the video in the stream. - **`AUDIO`**: The group ID for the audio rendition. - **`VIDEO`**: The group ID for the video rendition. - **`SUBTITLES`**: The group ID for the subtitles rendition. - **`CLOSED-CAPTIONS`**: The group ID for the closed captions rendition. - **`#EXT-X-I-FRAME-STREAM-INF`**: Specifies an I-frame variant stream. - **`#EXT-X-SESSION-DATA`**: Specifies arbitrary session data. - **`#EXT-X-SESSION-KEY`**: Specifies a master key for the playlist. ### Other Tags - **`#EXT-X-DATERANGE`**: Associates a date range with a set of attributes. - **`#EXT-X-START`**: Indicates a preferred starting point for the playlist. - **`#EXT-X-SERVER-CONTROL`**: Provides information to the client about the server's capabilities. - **`#EXT-X-PART-INF`**: Provides information about the partial segments of the playlist. - **`#EXT-X-RENDITION-REPORT`**: Provides a report of the renditions that are currently being played. - **`#EXT-X-SKIP`**: Skips a number of segments from the beginning of the playlist. - **`#EXT-X-PRELOAD-HINT`**: Hints to the client that it should preload a particular resource.