A. Surveillance video systems
sequence. For any traffic surveillance system, vehicle
vehicle movements. But, Vehicle segmentation in traffic
illumination variations. To solve this issue, an unsupervised
proposed for real time objects segmentation. In this work,
background/foreground. The segmentation time taken by the
neural network is improved by implementing it in FPGA kit.
background. A high cost is involved in reducing time
complexity [16]. Followed by this, [17]Appiah et. Al proposed
an integrated hardware implementation of moving object
segmentation in real time video stream under varying lighting
conditions. Two algorithms for multimodal background
modelling and connected component analysis is implemented
on a single chip FPGA. This method segments objects under
varying illumination condition at high processing speed. The
two algorithms described so far do not take raining issue into
account. Under raining situation, shadows and colour
reflections are the major problems to be tackled. A
conventional video object segmentation algorithm that
combines the background construction-based video object
segmentation and the foreground extraction-based video
object segmentation has been proposed. The foreground is
separated from the background using histogram-based change
detection technique and object regions are segmented
accurately by detecting the initial moving object masks based
on a frame difference mask. Shadow and colour reflection
regions are removed by diamond window mask and colour
analysis of moving object respectively. Segmentation of
moving objects are refined by morphological operations. The
segmentation results of moving objects under rainy situations.In the future, we will adaptively
obtain the threshold and adjustthe content of the video
automatically. Later, Chien et al [19] proposed a video object
segmentation and tracking technique for smart cameras in
visual surveillance networks. A multi-background model
based on threshold decision algorithm for video object
segmentation under drastic changes in illumination and
background clutter has been developed. In this method, the
threshold is selected robustly without user requirement and it
is different from per pixel background model which avoids
possible error propagations. Another algorithm for extracting
objects from videos captured by static camera has been
proposed to solve issues like waving tree, camouflage region
and sleeping is also proposed [20]. In this method, reference
background is obtained by averaging of some initial frames.
Temporal processing for object extraction do not consider
spatial correlation amongst the moving objects across frames.
Hence, an approximate motion field is derived using the
background subtraction and temporal difference mechanism.
The background model adapts temporal changes (swaying
trees, rippling water, etc) which extract the complementary
object in the scene.
using [18] is shown in fig.2.对于交通检测来说,最重要的就是分类各种各样的交通工具,但是,因为物体总是在运动的原因,所以还是很难识别。所以为了解决这个问题,一个无监督的神经网络被我们用来作为视频中前景色和背景色的适应性模型和像素的分类器。这个神经网络的运算时间可以把他装在fgpa上来减少,虽然这个神经网络作为“筛除背景”的方法取得了很高的分类效果,但是只能在光影变化不大和背景几乎不动的情况下使用,同时,减少时间复杂度的成本很高的,所以,Appiah et. Al提出了一种可在集成硬件上实行的算法,这两种算法在单核fgpa上就能实现,而且它很好地解决了光线问题。但是他没有解决雨天的问题,在雨天,阴影和光线的反射是最主要的问题。传统的算法将基于架构的背景分类和分离出的前景物体混合在一起。而前景应该利用基于“直方图”改变的侦测技术,目标区域也应该被分割出来,方法是侦测最初的移动物体基于移动物体的掩模和帧差异的掩码上(这是什么意思,目前没搞明白)。反正他说阴影和颜色反射的部分会被一个diamond window mask和颜色分析移动的目标算法分别来处理。这是一种分形几何的算法,移动中需要分割的物体被这种算法给限制了,在fig2中结果被呈现了出来。在未来,我们让算法自动适应性地调整“阈值”和“调整的内容”。之后,chien提出了一种对小型照相机的视觉神经网络的算法,在这种方法中,“阈值”不需要使用者的帮助就能鲁棒地给出,而且它与逐像素的算法还不同,避免了可能的错误宣传??(啥意思,不懂)。还有一种算法是使用静态相机的,专门用来捕捉正在摇晃的树,还有一些伪装的东西。初始化时利用一些初始帧的平均值(什么意思??),但是这种算法没有考虑空间相关性,尤其是那些逐帧移动的物体??。
个人结合这种算法的那张效果图,觉得就是可以过滤掉光影效果,仅留存真正的目标。
最后一段话真的看不懂了,所以就直接谷歌翻译了????
因此,使用该推导出近似运动场
背景减法和时间差分机制。
背景模型适应时间变化(摇摆
树木,涟漪水等)提取互补
场景中的物体。????
B. Generic video sequences
Moving foreground object extraction from a given generic
video shot is one of the vital tasks for content representation
and retrieval in many computer vision applications. An
iterative method based on energy minimization has been
proposed for segmenting the primary moving object efficiently
from moving camera video sequences. Initial object
segmentation obtained using graph-cut is improved repeatedly
by the features extracted over a set of neighbouring frames
[21]. Thus, this iterative method can efficiently segment the
objects in video shots captured on a moving camera. A
conditional random field model based video object
segmentation system, capable of segmenting multiple moving
objects from complex background has been proposed [22]. In
this work, a complementary property of point and region
trajectories is utilized effectively by transferring the labels of
sparse point trajectories to region trajectories. Region
trajectories based on shape consistency provides robust design
to segment spatially overlapping region trajectories. As region
trajectories are extracted from hierarchical image over
segmentation, it segments meaningful regions over time.
time and computational complexity. Unsupervised
segmentation of moving camera video sequence using inter
frame change detection has been proposed [23].
通用视频序列
这里提到了一种“迭代算法”,他的初始化就是通过一开始的几帧的图片分割,从一些相邻帧中提取的元素,所以这种算法可以从“移动的相机”中提取信息???论文22中提起了个
基于条件随机场模型的视频对象
分割系统,能够分割多个移动
已经提出了来自复杂背景的物体(???谷歌翻译结果)
论文22主要提及了从稀疏轨迹到稠密轨迹的算法?
论文23提及的是无监督学习方法?