FreeRDP/libfreerdp/codec/rfx_differential.h

51 lines
1.3 KiB
C

/**
* FreeRDP: A Remote Desktop Protocol Implementation
* RemoteFX Codec Library - Differential Encoding
*
* Copyright 2011 Vic Lee
*
* 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.
*/
#ifndef FREERDP_LIB_CODEC_RFX_DIFFERENTIAL_H
#define FREERDP_LIB_CODEC_RFX_DIFFERENTIAL_H
#include <freerdp/codec/rfx.h>
#include <freerdp/api.h>
static INLINE void rfx_differential_decode(INT16* WINPR_RESTRICT buffer, size_t size)
{
INT16* ptr = buffer;
INT16* end = &buffer[size - 1];
while (ptr != end)
{
ptr[1] += ptr[0];
ptr++;
}
}
static INLINE void rfx_differential_encode(INT16* WINPR_RESTRICT buffer, size_t size)
{
INT16 n1 = buffer[0];
for (size_t x = 0; x < size - 1; x++)
{
INT16* dst = &buffer[x + 1];
const INT16 n2 = *dst;
*dst -= n1;
n1 = n2;
}
}
#endif /* FREERDP_LIB_CODEC_RFX_DIFFERENTIAL_H */