Low level header functions on single components
[Low level access to single components]

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Detailed Description

Remarks:

Typically used after all other header settings are correct.

Do use p_get_comp_buffer_size() to determine buffer sizes. The functions support subsample factors which are not a multiple of the file image size. The component size is rounded UP.

Functions
int	p_mod_add_comp (pT_header *header)
int	p_get_comp_by_name (const pT_header *header, const char *name)
int	p_get_num_comps (const pT_header *header)
pT_status	p_mod_set_comp_2 (pT_header *header, const int comp, const char *name, const pT_data_fmt file_data_fmt, const int pix_subsample, const int line_subsample, const int multiplex_factor)
pT_status	p_mod_rm_comp (pT_header *header, const int comp)
pT_status	p_mod_rm_extra_comps (pT_header *header)
pT_status	p_get_comp_2 (const pT_header *header, const int comp, char *name, pT_data_fmt *file_data_fmt, int *pix_subsample, int *line_subsample, int *multiplex_factor)
pT_status	p_get_comp_buffer_size (const pT_header *header, const int comp, int *width, int *height)

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Function Documentation

int p_mod_add_comp (  pT_header *  header  )

Add a component to the header structure Component properties need to be set by p_mod_comp() Returns: component id. -1 if pfspd header full

int p_get_comp_by_name (  const pT_header *  header, const char *  name )

Uses the name to find the component id in header Returns -1 if not found

int p_get_num_comps (  const pT_header *  header  )

Returns the total number of components from the header

pT_status p_mod_set_comp_2 (  pT_header *  header, const int  comp, const char *  name, const pT_data_fmt  file_data_fmt, const int  pix_subsample, const int  line_subsample, const int  multiplex_factor )

Sets all properties of comp in header The multiplex factor is typically 1 for Y, 2 for U/V.

pT_status p_mod_rm_comp (  pT_header *  header, const int  comp )

Remove a comp from header Shall only be used for extra components No operation for component id -1

pT_status p_mod_rm_extra_comps (  pT_header *  header  )

Remove all "extra" components from header

pT_status p_get_comp_2 (  const pT_header *  header, const int  comp, char *  name, pT_data_fmt *  file_data_fmt, int *  pix_subsample, int *  line_subsample, int *  multiplex_factor )

Retrieves all properties of component comp from header name string allocated by caller, length: P_SCOM_CODE+1 Any output parameters may be NULL (no value returned)

pT_status p_get_comp_buffer_size (  const pT_header *  header, const int  comp, int *  width, int *  height )

Return height and width of comp buffer. This is the minimum size of a buffer that can be used by the read/write field/frame functions. For interlaced files this is the size of a field. For progressive files this is the size of a frame.

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