Media Types (Windows CE 5.0)
DirectShow uses the AM_MEDIA_TYPE structure to describe media samples.
This structure includes GUID fields for major type, subtype, and format type, as well as fields specifying other properties of the sample, such as whether the samples are compressed.
The following sections summarize the major type and subtype options registered by DirectShow. These media types are defined in the header file Uuids.h.
Media Types with No Subtype
The following table describes the media types with no subtype.
| Type | Description |
|---|---|
| MEDIATYPE_AnalogAudio | Analog audio connection. |
| MEDIATYPE_File | Media type is a file, used closed captions. |
| MEDIATYPE_Interleaved | Data is interleaved, used by Digital Video (DV). |
| MEDIATYPE_Midi | Data is MIDI format. |
| MEDIATYPE_ScriptCommand | Data is a script command, used by closed captions. |
| MEDIATYPE_Text | Data is text. |
| MEDIATYPE_Timecode | Data is timecode data. |
Audio Media Types
The wFormatTag member in the WAVEFORMATEX structure specifies the audio format type.
The format type is generally FORMAT_WaveFormatEx. Media samples are generally whole number of samples as specified in the wBitsPerSample member in the WAVEFORMATEX structure. This is not necessarily true for MPEG audio samples that can come from packetized streams and are therefore not necessarily packaged on sample/frame boundaries.
For MPEG audio the time stamp in a media sample is the time stamp for the first frame whose first byte is contained in the media sample.
Media subtypes are defined for each wFormatTag as follows:
- The Data1 subfield of the Media Subtype is the same as the wFormatTag value.
- The Data 2 field is 0.
- The Data 3 field is 0x0010.
- The Data 4 field is 0x80, 0x00, 0x00, 0xAA, 0x00, 0x38, 0x9B, 0x71.
Thus, for PCM audio the subtype GUID would be:
{00000001-0000-0010-8000-00AA00389B71}
Older filters may still use GUID_NULL as the subtype so this should be checked for. However, registration of a filter with the explicit subtype greatly improves the speed of graph loading, especially when the given filter is not required.
The CreateAudioMediaType function can be used to create an AM_MEDIA_TYPE structure from a WAVEFORMATEX Structure.
The following table describes the audio media subtypes.
| MEDIATYPE_Audio | Data is audio |
|---|---|
| MEDIASUBTYPE_PCMAudio | PCM audio |
| MEDIASUBTYPE_MPEG1Packet | MPEG1 Audio Packet |
| MEDIASUBTYPE_MPEG1Payload | MPEG1 Audio Payload |
Line 21 Media Types
The following table describes the line 21 closed captioning media subtypes.
| MEDIATYPE_AUXLine21Data | Data is line 21 type, used by closed captions |
|---|---|
| MEDIASUBTYPE_Line21_BytePair | Line 21 data as byte pairs |
| MEDIASUBTYPE_Line21_GOPPacket | Line 21 data in DVD GOP Packet |
| MEDIASUBTYPE_Line21_VBIRawData | Line 21 data in raw VBI format |
MPEG-2 Media Types
The following table describes the MPEG-2 media subtypes.
| MEDIATYPE_MPEG2_PES | Data is MPEG-2 format, used by DVD |
|---|---|
| MEDIASUBTYPE_DVD_SUBPICTURE | Subpicture data |
| MEDIASUBTYPE_DOLBY_AC3 | Dolby data |
| MEDIASUBTYPE_MPEG2_AUDIO | MPEG-2 audio data |
| MEDIASUBTYPE_DVD_LPCM_AUDIO | DVD audio data |
Stream Media Types
Time stamps are byte positions * 10000000 (notionally 1 byte per second) rather than real times.
The following table describes the stream media subtypes.
| MEDIATYPE_Stream | Data is a non-time stamped byte stream |
|---|---|
| MEDIASUBTYPE_Avi | Data from AVI file |
| MEDIASUBTYPE_WAVE | Data from WAV file |
| MEDIASUBTYPE_AU | Data from AU file |
| MEDIASUBTYPE_AIFF | Data from AIFF file |
| MEDIASUBTYPE_MPEG1Video | MPEG video |
| MEDIASUBTYPE_MPEG1System | MPEG system |
| MEDIASUBTYPE_MPEG1VideoCD | MPEG video CD |
| MEDIASUBTYPE_MPEG1Audio | MPEG audio |
| MEDIASUBTYPE_DssVideo | Dss Video |
| MEDIASUBTYPE_DssAudio | Dss Audio |
Video Media Types
The following table describes the video media subtypes.
| MEDIATYPE_Video | Data is video |
|---|---|
| MEDIASUBTYPE_YVU9 | Standard YVU9 format uncompressed data.
A planar YUV format. A Y sample at every pixel, a U and V sample at every fourth pixel horizontally on each line; a Y sample on every vertical line, a U and V sample at every fourth vertical line. 9 bits per pixel. |
| MEDIASUBTYPE_Y411 | YUV 411 format data.
Same as Y41P. |
| MEDIASUBTYPE_Y41P | Y41P format data.
A packed YUV format. A Y sample at every pixel, a U and V sample at every fourth pixel horizontally on each line; every vertical line sampled. Byte ordering (lowest first) is U0, Y0, V0, Y1, U4, Y2, V4, Y3, Y4, Y5, Y6, Y7, where the suffix 0 is the leftmost pixel and increasing numbers are pixels increasing left to right. Each 12-byte block is 8 image pixels. |
| MEDIASUBTYPE_YUY2 | YUY2 format data.
Same as UYVY but with different pixel ordering. Byte ordering (lowest first) is Y0, U0, Y1, V0, Y2, U2, Y3, V2, Y4, U4, Y5, V4, where the suffix 0 is the leftmost pixel and increasing numbers are pixels increasing left to right. Each 4-byte block is 2 image pixels. |
| MEDIASUBTYPE_YVYU | YVYU format data.
A packed YUV format. Same as UYVY but with different pixel ordering. Byte ordering (lowest first) is Y0, V0, Y1, U0, Y2, V2, Y3, U2, Y4, V4, Y5, U4, where the suffix 0 is the leftmost pixel and increasing numbers are pixels increasing left to right. Each 4-byte block is 2 image pixels. |
| MEDIASUBTYPE_UYVY | UYVY format data. A packed YUV format. A Y sample at every pixel, a U and V sample at every second pixel horizontally on each line; every vertical line sampled. Probably the most popular of the various YUV 4:2:2 formats. Byte ordering (lowest first) is U0, Y0, V0, Y1, U2, Y2, V2, Y3, U4, Y4, V4, Y5, where the suffix 0 is the leftmost pixel and increasing numbers are pixels increasing left to right. Each 4-byte block is 2 image pixels. |
| MEDIASUBTYPE_Y211 | YUV 211 format data.
A packed YUV format. A Y sample at every second pixel, a U and V sample at every fourth pixel horizontally on each line; every vertical line sampled. Byte ordering (lowest first) is Y0, U0, Y2, V0, Y4, U4, Y6, V4, Y8, U8, Y10, V8, where the suffix 0 is the leftmost pixel and increasing numbers are pixels increasing left to right. Each 4-byte block is 4 image pixels. |
| MEDIASUBTYPE_CLJR | Cirrus Logic Jr YUV 411 format with less than 8 bits per Y, U, and V sample.
A Y sample at every pixel, a U and V sample at every fourth pixel horizontally on each line; every vertical line sampled. |
| MEDIASUBTYPE_IF09 | Indeo produced YVU9 format with additional information about differences from the last frame. 9.5 bits per pixel but reported as 9. |
| MEDIASUBTYPE_MJPG | Motion JPEG (MJPG) compressed video. |
| MEDIASUBTYPE_TVMJ | TrueVision MJPG format. |
| MEDIASUBTYPE_WAKE | MJPG format produced by some cards. |
| MEDIASUBTYPE_CFCC | MJPG format produced by some cards. |
| MEDIASUBTYPE_IJPG | Intergraph JPEG format. |
| MEDIASUBTYPE_Plum | Plum MJPG format. |
| MEDIASUBTYPE_RGB1 | RGB 1 bit per pixel. Palettized. |
| MEDIASUBTYPE_RGB4 | RGB 4 bits per pixel. Palettized. |
| MEDIASUBTYPE_RGB8 | RGB 8 bits per pixel. Palettized. |
| MEDIASUBTYPE_RGB565 | 565 format of RGB, 16 bits per pixel. Uncompressed RGB samples. |
| MEDIASUBTYPE_RGB555 | 555 format of RGB, 16 bits per pixel. Uncompressed RGB samples. |
| MEDIASUBTYPE_RGB24 | RGB 24 bits per pixel. Uncompressed RGB samples. |
| MEDIASUBTYPE_RGB32 | RGB 32 bits per pixel. Uncompressed RGB samples. |
| MEDIASUBTYPE_Overlay | Video delivered using hardware overlay. |
| MEDIASUBTYPE_dvsd | Standard DV format. |
| MEDIASUBTYPE_dvhd | High Definition DV format. |
| MEDIASUBTYPE_dvsl | Long Play DV format. |
| MEDIASUBTYPE_MPEG1Packet | MPEG1 Video Packet. |
| MEDIASUBTYPE_MPEG1Payload | MPEG1 Video Payload. |
| MEDIASUBTYPE_VideoPort | Data is video port data, used with DVD. |
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