FreeRDP/libfreerdp/primitives/prim_YCoCg.c
2022-03-03 11:26:48 +01:00

75 lines
2.3 KiB
C

/* FreeRDP: A Remote Desktop Protocol Client
* YCoCg<->RGB Color conversion operations.
* vi:ts=4 sw=4:
*
* (c) Copyright 2014 Hewlett-Packard Development Company, L.P.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <freerdp/config.h>
#include <freerdp/types.h>
#include <freerdp/primitives.h>
#include "prim_internal.h"
/* helper function to convert raw 8 bit values to signed 16bit values.
*/
static INT16 convert(UINT8 raw, int shift)
{
const int cll = shift - 1; /* -1 builds in the /2's */
return (INT16)((INT8)(raw << cll));
}
/* ------------------------------------------------------------------------- */
static pstatus_t general_YCoCgToRGB_8u_AC4R(const BYTE* pSrc, INT32 srcStep, BYTE* pDst,
UINT32 DstFormat, INT32 dstStep, UINT32 width,
UINT32 height, UINT8 shift, BOOL withAlpha)
{
UINT32 x, y;
const DWORD formatSize = GetBytesPerPixel(DstFormat);
fkt_writePixel writePixel = getPixelWriteFunction(DstFormat, TRUE);
for (y = 0; y < height; y++)
{
const BYTE* sptr = &pSrc[srcStep * y];
BYTE* dptr = &pDst[dstStep * y];
for (x = 0; x < width; x++)
{
/* Note: shifts must be done before sign-conversion. */
const INT16 Cg = convert(*sptr++, shift);
const INT16 Co = convert(*sptr++, shift);
const INT16 Y = *sptr++; /* UINT8->INT16 */
const INT16 T = Y - Cg;
const INT16 B = T + Co;
const INT16 G = Y + Cg;
const INT16 R = T - Co;
BYTE A = *sptr++;
if (!withAlpha)
A = 0xFFU;
dptr = writePixel(dptr, formatSize, DstFormat, CLIP(R), CLIP(G), CLIP(B), A);
}
}
return PRIMITIVES_SUCCESS;
}
/* ------------------------------------------------------------------------- */
void primitives_init_YCoCg(primitives_t* prims)
{
prims->YCoCgToRGB_8u_AC4R = general_YCoCgToRGB_8u_AC4R;
}