dsp_h263_loopback.rar_H. 263_H263

/* ======================================================================== */ /* NAME */ /* chroma_resampling.c */ /* */ /* DESCRIPTION */ /* This file contains chroma resampling routines for use with the ZENO */ /* Video Port. */ /* All these routines have been written using the DMA streaming (dstr) */ /* interface. Specifically, it contains the following APIs: */ /* YUV422to420v() - This routine performs the vertical part of chroma */ /* resampling in going from 4:2:2 to 4:2:0 */ /* YUV420to422v() - This routine performs the vertical part of chroma */ /* resampling in going from 4:2:0 to 4:2:2 */ /* ------------------------------------------------------------------------ */ /* Copyright (c) 2002 Texas Instruments, Incorporated. */ /* All Rights Reserved. */ /* ======================================================================== */ /* ======================================================================== */ /* basic header includes */ /* ======================================================================== */ #include <stdio.h> #include <stdlib.h> #include <std.h> /* ======================================================================== */ /* CSL includes */ /* ======================================================================== */ #include <csl.h> #include <csl_irq.h> #include <csl_dat.h> #include <csl_cache.h> #include <csl_legacy.h> /* ======================================================================== */ /* include files for DMA streaming and scaling kernel that performs */ /* vertical chroma resampling */ /* ======================================================================== */ #include "dstr_2d.h" #include "scale_v2_h.h" /* ======================================================================== */ /* Image and scratch buffer structures for pre-post processing operations */ /* ======================================================================== */ typedef struct { unsigned char *Y_data; unsigned char *Cb_data; unsigned char *Cr_data; } IMG; typedef struct { unsigned char *in_data; int size; }SCRATCH; /* ======================================================================== */ /* YUV422to420v() - vertical chroma resampling of source */ /* INTERFACE: */ /* void YUV422to420v( */ /* void *in, */ /* void *out, */ /* int width, */ /* int height, */ /* void *scratch */ /* ); */ /* RETURN VALUE: None */ /* PARAMETERS: */ /* in - pointer to input data(planar Y:Cb:Cr 4:2:2 format) */ /* out - pointer to output data (planar Y:Cb:Cr 4:2:0 format) */ /* width - pixels per line of source luma */ /* height - number of lines of source luma */ /* scratch - pointer to scratch buffer in DSP's internal memory(used by */ /* dstr interface for DMA operation) */ /* ======================================================================== */ void YUV422to420v(void *in,void *out,int width,int height,void *scratch) { int i,err_code; unsigned int id; /* ==================================================================== */ /* External Buffer pointers */ /* ==================================================================== */ unsigned char *Cr_in,*Cb_in; unsigned char *Cr_out,*Cb_out; /* ==================================================================== */ /* Internal scratch pointer */ /* ==================================================================== */ unsigned char *int_mem; /* ==================================================================== */ /* dma stream objects */ /* ==================================================================== */ dstr_t din_Cr,din_Cb,dout_Cr,dout_Cb; /* ==================================================================== */ /* Internal Buffer pointers */ /* ==================================================================== */ unsigned char *Cb_in_int,*Cr_in_int,*Cb_out_int,*Cr_out_int; unsigned char *Cb_in_sc,*Cr_in_sc,*Cb_out_sc,*Cr_out_sc; /* ==================================================================== */ /* get pointers to input and output data(in external memory) */ /* ==================================================================== */ Cr_in = ((IMG *)in)->Cr_data; Cb_in = ((IMG *)in)->Cb_data; Cr_out = ((IMG *)out)->Cr_data; Cb_out = ((IMG *)out)->Cb_data; /* ==================================================================== */ /* setup the internal scratch(work) buffers */ /* ==================================================================== */ int_mem = ((SCRATCH *)scratch)->in_data; Cb_in_sc = int_mem; Cr_in_sc = int_mem + 4 * width; Cb_out_sc = int_mem + 8 * width; Cr_out_sc = int_mem + 10 * width; /* ==================================================================== */ /* The luminance data is not processed at all */ /* Check if the user passed the same buffer pointers for input and */ /* output Y, else copy the data from input to output buffer */ /* ==================================================================== */ if(((IMG *)in)->Y_data != ((IMG *)out)->Y_data){ for(i=0;i<height;i++){ id = DAT_copy(((IMG *)in)->Y_data +i*width,int_mem,width); DAT_wait(id); id = DAT_copy(int_mem,((IMG *)out)->Y_data +i*width,width); } } DAT_wait(id); /* ==================================================================== */ /* Set up the DMA streams */ /* ==================================================================== */ /* ==================================================================== */ /* open input chroma streams with the following parameters: */ /* size of external buffer --> (width/2)*height (4:2:2 data) */ /* size of internal buffer --> width*4 (work buffer needs to be atleast*/ /* width*2 but we overallocate here) */ /* size of each get --> width ( bring in two lines of chroma, */ /* each width/2 pixels) */ /* number of gets --> 1 */ /* external pointer stride --> width (stride by an amount equal to */ /*