/* 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)

{

  const DWORD formatSize = FreeRDPGetBytesPerPixel(DstFormat);

  fkt_writePixel writePixel = getPixelWriteFunction(DstFormat, TRUE);

  for (UINT32 y = 0; y < height; y++)

  {

    const BYTE* sptr = &pSrc[srcStep * y];

    BYTE* dptr = &pDst[dstStep * y];

    for (UINT32 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;

}