Allocate Pin Buffer

CTransformFilter::DecideBufferSize

ALLOCATOR_PROPERTIES Structure

和CMediaType::SetSampleSize有關

如果沒對映好，送到pin腳的資料就會少

DirectShow MediaType

AM_MEDIA_TYPE http://msdn2.microsoft.com/en-us/library/aa930737.aspx

typedef struct _MediaType{
GUID majortype;
GUID subtype;
BOOL bFixedSizeSamples;
BOOL bTemporalCompression;
ULONG lSampleSize;
GUID formattype; .
IUnknown* pUnk;
ULONG cbFormat;
/* [size_is] */ BYTE __RPC_FAR* pbFormat;
} AM_MEDIA_TYPE;

formattype
Registered (GUID) format type.
pbFormat
Pointer to the format section of the media type. The layout of this is determined by the format type GUID.
-> 指向這個media type的structure


CMediaType::SetFormatType -> specifies the format type
CMediaType::SetFormat -> initializes the format block.

RTSP 簡圖

Client               Server
  |                    |
  | ---- DESCRIBE ---> |
  | <----------------- |SDP, video type, length...
  |                    |
  | ----- SETUP -----> |client address, port
  | <----------------- |server address, port
  |                    |
  | ------ PLAY -----> |
  | <----------------- |
  |                    |
  | <----------------- |
  |    Media Stream    | RTP on UDP
  | <----------------- |
  |                    |
  | ----- PAUSE -----> |
  | <----------------- |
  |                    |
  | ---- TEARDOWN ---> |
  | <----------------- |
  |                    |

Real Time Streaming Protocol from Wikipedia