| /* |
| * Copyright (c) 2012 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/main/source/denoising.h" |
| #include "webrtc/system_wrappers/interface/trace.h" |
| |
| #include <string.h> |
| |
| namespace webrtc { |
| // Down-sampling in time (unit: number of frames) |
| enum { kSubsamplingTime = 0 }; |
| // Sub-sampling in width (unit: power of 2. |
| enum { kSubsamplingWidth = 0 }; |
| // Sub-sampling in height (unit: power of 2) |
| enum { kSubsamplingHeight = 0 }; |
| // (Q8) De-noising filter parameter |
| enum { kDenoiseFiltParam = 179 }; |
| // (Q8) 1 - filter parameter |
| enum { kDenoiseFiltParamRec = 77 }; |
| // (Q8) De-noising threshold level |
| enum { kDenoiseThreshold = 19200 }; |
| |
| VPMDenoising::VPMDenoising() |
| : id_(0), |
| moment1_(NULL), |
| moment2_(NULL) { |
| Reset(); |
| } |
| |
| VPMDenoising::~VPMDenoising() { |
| if (moment1_) { |
| delete [] moment1_; |
| moment1_ = NULL; |
| } |
| |
| if (moment2_) { |
| delete [] moment2_; |
| moment2_ = NULL; |
| } |
| } |
| |
| int32_t VPMDenoising::ChangeUniqueId(const int32_t id) { |
| id_ = id; |
| return VPM_OK; |
| } |
| |
| void VPMDenoising::Reset() { |
| frame_size_ = 0; |
| denoise_frame_cnt_ = 0; |
| |
| if (moment1_) { |
| delete [] moment1_; |
| moment1_ = NULL; |
| } |
| |
| if (moment2_) { |
| delete [] moment2_; |
| moment2_ = NULL; |
| } |
| } |
| |
| int32_t VPMDenoising::ProcessFrame(I420VideoFrame* frame) { |
| assert(frame); |
| int32_t thevar; |
| int k; |
| int jsub, ksub; |
| int32_t diff0; |
| uint32_t tmp_moment1; |
| uint32_t tmp_moment2; |
| uint32_t tmp; |
| int32_t num_pixels_changed = 0; |
| |
| if (frame->IsZeroSize()) { |
| WEBRTC_TRACE(webrtc::kTraceError, webrtc::kTraceVideoPreocessing, id_, |
| "zero size frame"); |
| return VPM_GENERAL_ERROR; |
| } |
| |
| int width = frame->width(); |
| int height = frame->height(); |
| |
| /* Size of luminance component */ |
| const uint32_t y_size = height * width; |
| |
| /* Initialization */ |
| if (y_size != frame_size_) { |
| delete [] moment1_; |
| moment1_ = NULL; |
| |
| delete [] moment2_; |
| moment2_ = NULL; |
| } |
| frame_size_ = y_size; |
| |
| if (!moment1_) { |
| moment1_ = new uint32_t[y_size]; |
| memset(moment1_, 0, sizeof(uint32_t)*y_size); |
| } |
| |
| if (!moment2_) { |
| moment2_ = new uint32_t[y_size]; |
| memset(moment2_, 0, sizeof(uint32_t)*y_size); |
| } |
| |
| /* Apply de-noising on each pixel, but update variance sub-sampled */ |
| uint8_t* buffer = frame->buffer(kYPlane); |
| for (int i = 0; i < height; i++) { // Collect over height |
| k = i * width; |
| ksub = ((i >> kSubsamplingHeight) << kSubsamplingHeight) * width; |
| for (int j = 0; j < width; j++) { // Collect over width |
| jsub = ((j >> kSubsamplingWidth) << kSubsamplingWidth); |
| /* Update mean value for every pixel and every frame */ |
| tmp_moment1 = moment1_[k + j]; |
| tmp_moment1 *= kDenoiseFiltParam; // Q16 |
| tmp_moment1 += ((kDenoiseFiltParamRec * ((uint32_t)buffer[k + j])) << 8); |
| tmp_moment1 >>= 8; // Q8 |
| moment1_[k + j] = tmp_moment1; |
| |
| tmp_moment2 = moment2_[ksub + jsub]; |
| if ((ksub == k) && (jsub == j) && (denoise_frame_cnt_ == 0)) { |
| tmp = ((uint32_t)buffer[k + j] * |
| (uint32_t)buffer[k + j]); |
| tmp_moment2 *= kDenoiseFiltParam; // Q16 |
| tmp_moment2 += ((kDenoiseFiltParamRec * tmp) << 8); |
| tmp_moment2 >>= 8; // Q8 |
| } |
| moment2_[k + j] = tmp_moment2; |
| /* Current event = deviation from mean value */ |
| diff0 = ((int32_t)buffer[k + j] << 8) - moment1_[k + j]; |
| /* Recent events = variance (variations over time) */ |
| thevar = moment2_[k + j]; |
| thevar -= ((moment1_[k + j] * moment1_[k + j]) >> 8); |
| // De-noising criteria, i.e., when should we replace a pixel by its mean. |
| // 1) recent events are minor. |
| // 2) current events are minor. |
| if ((thevar < kDenoiseThreshold) |
| && ((diff0 * diff0 >> 8) < kDenoiseThreshold)) { |
| // Replace with mean. |
| buffer[k + j] = (uint8_t)(moment1_[k + j] >> 8); |
| num_pixels_changed++; |
| } |
| } |
| } |
| |
| denoise_frame_cnt_++; |
| if (denoise_frame_cnt_ > kSubsamplingTime) |
| denoise_frame_cnt_ = 0; |
| |
| return num_pixels_changed; |
| } |
| |
| } // namespace |