webrtc/modules/video_processing/brighten.cc

/*
 *  Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
 *
 *  Use of this source code is governed by a BSD-style license
 *  that can be found in the LICENSE file in the root of the source
 *  tree. An additional intellectual property rights grant can be found
 *  in the file PATENTS.  All contributing project authors may
 *  be found in the AUTHORS file in the root of the source tree.
 */

#include "webrtc/modules/video_processing/brighten.h"

#include <stdlib.h>

namespace webrtc {
namespace VideoProcessing {

int32_t Brighten(VideoFrame* frame, int delta) {
  assert(frame);
  if (frame->IsZeroSize()) {
    return VPM_PARAMETER_ERROR;
  }
  if (frame->width() <= 0 || frame->height() <= 0) {
    return VPM_PARAMETER_ERROR;
  }

  int num_pixels = frame->width() * frame->height();

  int look_up[256];
  for (int i = 0; i < 256; i++) {
    int val = i + delta;
    look_up[i] = ((((val < 0) ? 0 : val) > 255) ? 255 : val);
  }

  uint8_t* temp_ptr = frame->buffer(kYPlane);

  for (int i = 0; i < num_pixels; i++) {
    *temp_ptr = static_cast<uint8_t>(look_up[*temp_ptr]);
    temp_ptr++;
  }
  return VPM_OK;
}

}  // namespace VideoProcessing
}  // namespace webrtc