公开(公告)号：US07405770B1

公开(公告)日：2008-07-29

申请号：US11116098

申请日：2005-04-27

申请人： Daniel Gudmunson

发明人： Daniel Gudmunson

IPC分类号： H04N5/21

CPC分类号： H04N5/21 ,  H04N5/85 ,  H04N5/911 ,  H04N9/7908 ,  H04N9/8042

摘要： An adaptive equalization method and system for reducing noise and distortion in a sampled video signal improves the quality of output video information in both consumer and professional applications. A multi-band equalizer applied to the sampled video information reduces noise and distortion artifacts in the sampled video information. The gains of each of the equalizer bands is adjusted dynamically by control outputs provided by a noise and distortion detector. The noise and distortion detector incorporates circuits for comparing the luminance of each plane on a per-pixel basis with neighboring pixels and also includes a pattern matching comparator that detects edge features by comparing each pixel and its neighbors with a set of predetermined patterns. The noise and distortion detection can be further confirmed by comparing the detection results across multiple frames and the equalizer gain values may be further selected by a result of a video motion type classification.

摘要翻译： 用于降低采样视频信号中的噪声和失真的自适应均衡方法和系统提高了消费者和专业应用中的输出视频信息的质量。 应用于采样视频信息的多频带均衡器减少采样视频信息中的噪声和失真伪像。 每个均衡器频带的增益由噪声和失真检测器提供的控制输出动态调整。 噪声和失真检测器包括用于将每个像素的每个平面的亮度与相邻像素进行比较的电路，并且还包括模式匹配比较器，其通过将每个像素及其邻居与一组预定模式进行比较来检测边缘特征。 可以通过比较多个帧的检测结果来进一步确认噪声和失真检测，并且可以通过视频运动类型分类的结果进一步选择均衡器增益值。

公开(公告)号：US07499106B1

公开(公告)日：2009-03-03

申请号：US11082346

申请日：2005-03-17

申请人： Daniel Gudmunson ,  John Melanson ,  Rahul Singh ,  Ahsan Chowdhury

发明人： Daniel Gudmunson ,  John Melanson ,  Rahul Singh ,  Ahsan Chowdhury

IPC分类号： H04L7/00

CPC分类号： H03L7/1974 ,  H03L7/08 ,  H03L7/0805 ,  H03L2207/50 ,  H04N5/12 ,  H04N5/213 ,  H04N5/765 ,  H04N5/85 ,  H04N7/0132 ,  H04N9/8042 ,  H04N9/896 ,  H04N21/4325 ,  H04N21/44004

摘要： A method and system for synchronizing video information derived from an asynchronously sampled video signals provide a mechanism for using asynchronous sampling in the front-end of digital video capture systems. A ratio between the sampling clock frequency and the source video clock frequency is computed via an all digital phase-lock loop (ADPLL) and either a video clock is generated from the ratio by another PLL, a number to clock converter or the ratio is used directly to provide digital synchronization information to downstream processing blocks. A sample rate converter (SRC) is provided in an interpolator that either acts as a sample position corrector at the same line rate as the received video, or by introducing an offset in the ADPLL, the video data can be converted to another line rate via the SRC.

摘要翻译： 用于同步从异步采样的视频信号导出的视频信息的方法和系统提供了在数字视频采集系统的前端中使用异步采样的机制。 通过全数字锁相环（ADPLL）计算采样时钟频率和源视频时钟频率之间的比例，并且视频时钟由另一个PLL的比率，数字到时钟转换器或使用的比率产生 直接向下游处理块提供数字同步信息。 在内插器中提供采样率转换器（SRC），其作为采样位置校正器以与接收的视频相同的线路速率，或者通过在ADPLL中引入偏移量，视频数据可以通过 SRC。

公开(公告)号：US07474724B1

公开(公告)日：2009-01-06

申请号：US11082347

申请日：2005-03-17

申请人： Daniel Gudmunson ,  John Melanson ,  Rahul Singh ,  Ahsan Chowdhury

发明人： Daniel Gudmunson ,  John Melanson ,  Rahul Singh ,  Ahsan Chowdhury

IPC分类号： H03D3/24

CPC分类号： H03L7/1974 ,  H03L7/08 ,  H03L7/0805 ,  H03L2207/50 ,  H04N5/12 ,  H04N5/213 ,  H04N5/765 ,  H04N5/85 ,  H04N7/0132 ,  H04N9/8042 ,  H04N9/896 ,  H04N21/4325 ,  H04N21/44004

摘要： A method and system for video-synchronous audio clock generation from an asynchronously sampled video signal provides a mechanism for maintaining synchronization of audio sampling in digital video-audio systems. A ratio between the sampling clock frequency and an audio reference frequency clock is computed via an all digital phase-lock loop (ADPLL) and an audio clock is generated from the ratio by another PLL or a number to clock converter. In systems where a sampling clock to source video clock ratio has been computed for recovering a video signal, the audio ratio can be computed directly from the video ratio.

摘要翻译： 用于从异步采样的视频信号产生视频同步音频时钟的方法和系统提供了一种用于维持数字视频 - 音频系统中音频采样同步的机制。 通过全数字锁相环（ADPLL）计算采样时钟频率和音频参考频率时钟之间的比例，并且通过另一PLL或数字到时钟转换器从该比率产生音频时钟。 在已经计算了用于恢复视频信号的源视频时钟比的采样时钟的系统中，可以从视频比率直接计算音频比。

公开(公告)号：US07158045B1

公开(公告)日：2007-01-02

申请号：US11088446

申请日：2005-03-24

申请人： Daniel Gudmunson ,  John Melanson ,  Rahul Singh ,  Ahsan Chowdhury

发明人： Daniel Gudmunson ,  John Melanson ,  Rahul Singh ,  Ahsan Chowdhury

IPC分类号： H04L7/00

CPC分类号： H03L7/0994 ,  H03L7/07 ,  H03L7/0805 ,  H03L7/197

摘要： A method and apparatus for maintaining an ideal frequency ratio between numerically-controlled frequency sources provides a mechanism for maintaining coherence between multiple synchronization references where a known ideal rational relationship between the sources is known. Multiple numerically controlled oscillators (NCOs) generate the multiple synchronization references, which may be clock signals or numeric phase representations and the outputs of the NCOs are compared with a ratiometric frequency comparator that determines whether there is an error in the ratio between the NCO outputs. The frequency of one of the NCOs is then adjusted with a frequency correction factor provided by the ratiometric frequency comparator. The NCO inputs can represent ratios of the synchronization reference frequencies to a fixed reference clock and the NCOs clocked by the fixed reference clock.

摘要翻译： 用于在数控频率源之间保持理想频率比的方法和装置提供了一种维持多个同步参考之间的相干性的机制，其中已知的源之间的理想的理性关系是已知的。 多个数控振荡器（NCO）产生多个同步参考，其可以是时钟信号或数字相位表示，并且将NCO的输出与比较率频率比较器进行比较，其确定NCO输出之间的比率是否存在误差。 然后用比例式频率比较器提供的频率校正因子来调整NCO之一的频率。 NCO输入可以表示同步参考频率与固定参考时钟的比率和由固定参考时钟计时的NCO。

公开(公告)号：US06769006B2

公开(公告)日：2004-07-27

申请号：US09781951

申请日：2001-02-14

申请人： Alexei Krouglov ,  Jie Zhou ,  Daniel Gudmunson

发明人： Alexei Krouglov ,  Jie Zhou ,  Daniel Gudmunson

IPC分类号： G06F752

CPC分类号： G06F7/535 ,  G06F1/0356 ,  G06F7/4873 ,  G06F2207/5355 ,  G06F2207/5356

摘要： A method and apparatus for the calculation of the reciprocal of a normalized mantissa M for a floating-point input number D. A formula for determining the minimum size for the look-up table in accordance with the required precision is provided, as well as formulas for calculating look-up table entries. The look-up table stores the initiation approximations and the correction coefficients, which are addressed by the corresponding number of the mantissa's most significant bits and used to obtain the initial approximation of the reciprocal by means of linear interpolation requiring one subtraction operation and one multiplication operation. The result of the linear interpolation may be fed to a Newton-Raphson iteration device requiring, for each iteration, two multiplication operations and one two's complement operation, thereby doubling the precision of the reciprocal.