Jove
Visualize
联系我们
JoVE
x logofacebook logolinkedin logoyoutube logo
关于 JoVE
概览领导团队博客JoVE 帮助中心
作者
出版流程编辑委员会范围与政策同行评审常见问题投稿
图书馆员
用户评价订阅访问资源图书馆顾问委员会常见问题
研究
JoVE JournalMethods CollectionsJoVE Encyclopedia of Experiments存档
教育
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab Manual教师资源中心教师网站
使用条款与条件
隐私政策
政策

相关概念视频

Upsampling01:22

Upsampling

216
Managing signal sampling rates is essential in digital signal processing to maintain signal integrity. A decimated signal, characterized by a reduced frequency range due to its lower sampling rate, can be upsampled by inserting zeros between each sample. This upsampling process expands the original spectrum and introduces repeated spectral replicas at intervals dictated by the new Nyquist frequency. To refine this zero-inserted sequence, it is passed through a lowpass filter with a cutoff...
216
Aliasing01:18

Aliasing

124
Accurate signal sampling and reconstruction are crucial in various signal-processing applications. A time-domain signal's spectrum can be revealed using its Fourier transform. When this signal is sampled at a specific frequency, it results in multiple scaled replicas of the original spectrum in the frequency domain. The spacing of these replicas is determined by the sampling frequency.
If the sampling frequency is below the Nyquist rate, these replicas overlap, preventing the original...
124
Downsampling01:20

Downsampling

140
When considering a sampled sequence with zero values between sampling instants, one can replace it by taking every N-th value of the sequence. At these integer multiples of N, the original and sampled sequences coincide. This process, known as decimation, involves extracting every N-th sample from a sequence, thereby creating a more efficient sequence.
The Fourier transform of the decimated sequence reveals a combination of scaled and shifted versions of the original spectrum. This...
140
Bandpass Sampling01:17

Bandpass Sampling

166
In signal processing, bandpass sampling is an effective technique for sampling signals that have most of their energy concentrated within a narrow frequency band. This type of signal is known as a bandpass signal. The key principle of bandpass sampling involves sampling the signal at a rate that is greater than twice the signal's bandwidth to prevent aliasing.
A bandpass signal has a spectrum with a lower frequency limit, denoted as ω1, and an upper frequency limit, denoted as ω2....
166
Sampling Theorem01:15

Sampling Theorem

311
In signal processing, the analysis of continuous-time signals, denoted as x(t), often involves sampling techniques to convert these signals into discrete-time signals. This process is essential for digital representation and manipulation. A critical component in sampling is the train of impulses, characterized by the sampling interval and the sampling frequency. The relationship between these parameters and the original signal's properties dictates the success of the sampling process.
311
Sampling Methods: Overview01:06

Sampling Methods: Overview

288
A sample refers to a smaller subset representative of a larger population. In analytical chemistry, studying or analyzing an entire population is often impractical or impossible. Therefore, samples are used to draw inferences and generalize the whole population. The sampling method selects individuals or items from a population to create a sample. Standard sampling methods include random, judgemental, systematic, stratified, and cluster sampling. 
In analytical chemistry, the choice of...
288

您也可能阅读

相关文章

通过共同作者、期刊和引用图与本文相关的文章。

排序
Same author

Efficient algorithm for optimal wavelength selection in photoacoustic spectral unmixing.

Biomedical optics express·2026
Same author

Polarization-sensitive optical coherence tomography-based fully-automated volumetric coronary fibrous cap characterization.

European heart journal. Imaging methods and practice·2026
Same author

Erratum: Wavenumber-space wavefront sensorless adaptive-optics for optical coherence tomography: publisher's note.

Biomedical optics express·2026
Same author

FUSION: A fast and uniform processing framework for whole-brain optical scattering tomography images.

bioRxiv : the preprint server for biology·2026
Same author

Wavenumber-space wavefront sensorless adaptive-optics for optical coherence tomography.

Biomedical optics express·2026
Same author

Development and characterization of a clinically viable metalens-enhanced optical endoscope.

Optics express·2025
Same journal

Gaussian-modulated continuous-variable quantum key distribution over 60 km fiber using an integrated silicon photonic receiver.

Optics letters·2026
Same journal

E2E-OCT: end-to-end joint learning model using optical coherence tomography images for vocal cord leukoplakia diagnosis.

Optics letters·2026
Same journal

Holographic generation of panoramic 3D scenes by concave ellipsoidal mirror reflection.

Optics letters·2026
Same journal

Dual-pilot phase recovery with pair-wise maximum-ratio combining for coherent PONs.

Optics letters·2026
Same journal

Mapping the whispering gallery modes of a CaF<sub>2</sub> disk resonator with half-tapered fibers to estimate the fundamental mode volume.

Optics letters·2026
Same journal

Quantitative estimation of deep-subwavelength scale via dark-field scattering axial energy concentration decay profiles.

Optics letters·2026
查看所有相关文章

相关实验视频

Updated: Jun 14, 2025

Sample Drift Correction Following 4D Confocal Time-lapse Imaging
10:04

Sample Drift Correction Following 4D Confocal Time-lapse Imaging

Published on: April 12, 2014

16.4K

样本倾斜用于通过角复合抑制斑点.

Bhaskara Rao Chintada, Pelham Keahey, Néstor Uribe-Patarroyo

    Optics letters
    |August 29, 2024
    PubMed
    概括
    此摘要是机器生成的。

    使用样本倾斜的角度复合抑制了光学连贯断层扫描 (OCT) 图像中的斑点噪声. 这种方法可以提高图像质量,而不需要对现有的海外国家和地区仪器进行硬件修改.

    更多相关视频

    Gain-compensation Methodology for a Sinusoidal Scan of a Galvanometer Mirror in Proportional-Integral-Differential Control Using Pre-emphasis Techniques
    09:01

    Gain-compensation Methodology for a Sinusoidal Scan of a Galvanometer Mirror in Proportional-Integral-Differential Control Using Pre-emphasis Techniques

    Published on: April 4, 2017

    8.6K
    Live Cell Imaging of F-actin Dynamics via Fluorescent Speckle Microscopy FSM
    19:16

    Live Cell Imaging of F-actin Dynamics via Fluorescent Speckle Microscopy FSM

    Published on: August 5, 2009

    15.9K

    相关实验视频

    Last Updated: Jun 14, 2025

    Sample Drift Correction Following 4D Confocal Time-lapse Imaging
    10:04

    Sample Drift Correction Following 4D Confocal Time-lapse Imaging

    Published on: April 12, 2014

    16.4K
    Gain-compensation Methodology for a Sinusoidal Scan of a Galvanometer Mirror in Proportional-Integral-Differential Control Using Pre-emphasis Techniques
    09:01

    Gain-compensation Methodology for a Sinusoidal Scan of a Galvanometer Mirror in Proportional-Integral-Differential Control Using Pre-emphasis Techniques

    Published on: April 4, 2017

    8.6K
    Live Cell Imaging of F-actin Dynamics via Fluorescent Speckle Microscopy FSM
    19:16

    Live Cell Imaging of F-actin Dynamics via Fluorescent Speckle Microscopy FSM

    Published on: August 5, 2009

    15.9K

    科学领域:

    • 生物医学光学 生物医学光学
    • 医疗成像医学成像

    背景情况:

    • 斑点噪声显著降低了光学连贯断层扫描 (OCT) 图像质量,阻碍了准确的解释.
    • 现有的基于硬件的斑点抑制技术需要对OCT系统进行复杂的修改.
    • 算法斑点抑制方法往往缺乏验证,因为缺乏物理上有意义的基本真理.

    研究的目的:

    • 引入一种新的,独立于硬件的方法,用于在OCT图像中抑制斑点.
    • 通过样本倾斜来证明角度复合的有效性,以减少噪音.
    • 为了验证利用物理信息图像注册的方法.

    主要方法:

    • 通过使用机动旋转阶段倾斜样本实现了角度复合.
    • 在不同的样本倾斜角度获得多重断层扫描.
    • 开发了一种以物理为基础的亲缘映射,以关联在不同倾斜角度获得的断层图,直接从测量数据中检索.

    主要成果:

    • 在OCT图像中通过角复合成功证明了斑点抑制.
    • 展示了样品倾斜可以有效提高图像质量,而不会改变OCT硬件.
    • 直接从获得的数据中验证了对物理信息相关的亲缘地图的检索.

    结论:

    • 使用机动阶段倾斜样本为OCT斑点抑制提供了有效的,无需硬件的解决方案.
    • 这种方法使得与现有的OCT仪器进行角度复合,从而提高图像的可解读性.
    • 基于物理学的亲缘映射方法为算法斑点减少提供了强有力的验证.