Abstract: For a compressed video stream formed of a sequence of compressed data packets, each compressed packet is assigned to a frame by processing the undecoded data packet. A frame includes packets. A first plurality of frames is assigned to a first sliding window and a second plurality of frames is assigned to a second sliding window. The first and second sliding windows have different frames. A first window indicator is calculated by determining a first indicator representing an average number of packets per frame within the first window, and/or a second indicator representing size information of the data within the first window. A second window indicator is calculated by determining a third indicator representing an average number of packets per frame within the second window, and/or a fourth indicator representing size information of the data within the second window. The first and the second window indicators are compared.

Abstract: Detecting a change between images is performed more effectively when a measure of change is used for the detection that depends on a length of the code blocks to which the images are individually entropy-encoded, and which are allocated to different sections of the respective image, since the length of these code blocks is also available without decoding. This uses the fact that the length or amount of data of a code block directly depends, in large parts, on the entropy and hence on the complexity of the allocated image section, and that changes between images are, with high probability, also reflected in a change of complexity.

Abstract: A better compromise between the dynamic range, the spatial resolution, the implementation outlay and the image quality is achieved if different subdivisions of the exposure interval into accumulation intervals are performed for different pixel sensors or pixels. In the event of more than one accumulation interval per exposure interval, the values detected in the accumulation intervals are summed to obtain the respective pixel value. Since the exposure effectively continues to take place for all pixels over the entire exposure interval, no impairment of the image quality arises, or no artifacts arise in image movements. All pixels undergo the same image blur on account of the movement. The additional hardware outlay compared with commercially available pixel sensors is either entirely non-existent or can be kept very small, depending on the implementation. Moreover, a reduction in the spatial resolution is not necessary since the pixels contribute equally to the image capturing.

Abstract: Where a quantized data value is produced by a first quantization of an input data value, followed by a first inverse quantization and subsequently by a second quantization and the first quantization has first quantization intervals and the second quantization has second quantization intervals, third quantization intervals are generated by displacing interval boundaries of the second quantization intervals, respectively, to the next interval boundaries of the first quantization intervals. A third reconstruction value is determined for the third quantization intervals such that the third reconstruction value lies within the associated third quantization intervals. A corrected data value is generated by a third inverse quantization of the quantized data value and the third inverse quantization is affirmed by the third quantization intervals containing the associated third reconstruction value.

Abstract: A method and a system for spatial scalable region of interest transcoding of JPEG2000 coded video frames for video surveillance systems. Based on a user defined ROI, the method transcodes HD frames into images in moderate resolution with a ROI in HD resolution. The transcoder extracts all packets belonging to the ROI or the lower resolution levels of the background from the JPEG2000 bitstream. Non-ROI packets of higher resolution levels are replaced by empty packets. The ROI is tracked using a mean shift algorithm to guarantee that always the correct image details are extracted in high resolution. Since the transcoding is performed by extracting and replacing packets of the codestream, an expensive re-encoding of the code-stream is not required. Thus, the transcoding technique is of low complexity and shows a short processing time. Combining the transcoding technique with mean shift tracking leads to a powerful video transcoding technique.

Abstract: A prediction error (eq[x,y]) is added to a predicted frame ({circumflex over (f)}[x,y]) or a predicted block for receiving a decoded frame (gq[x,y]) or a decoded block to be further used in a prediction loop by an encoder or to be sent to the output of a decoder. The reference frame (gq[x,y]) or the reference block includes a useful signal part and a noise signal part. The reference frame (gq[x,y]) or reference block pass through a dedicated noise reducing filter to reduce or eliminate the noise signal part of the reference frame (gq[x,y]) or reference block.

Abstract: A method and system for automatic object detection and subsequent object tracking in accordance with the object shape in digital video systems having at least one camera for recording and transmitting video sequences. In accordance with the method and system, an object detection algorithm based on a Gaussian mixture model and expanded object tracking based on Mean-Shift are combined with each other in object detection. The object detection is expanded in accordance with a model of the background by improved removal of shadows, the binary mask generated in this way is used to create an asymmetric filter core, and then the actual algorithm for the shape-adaptive object tracking, expanded by a segmentation step for adapting the shape, is initialized, and therefore a determination at least of the object shape or object contour or the orientation of the object in space is made possible.

Abstract: An input data stream coded using a first coding method and containing at least one coded digitized image is converted into an output data stream that is coded using a second coding method. The input data stream has first intra-blocks, each of which is coded in a first prediction mode of a plurality of first intra-prediction modes, and the output data stream has second intra-blocks, each of which is coded in a second prediction mode of a plurality of second intra-protection modes. The second prediction modes of one or more second intra-blocks are determined with the aid of the first prediction modes for one or more first intra-blocks and the second intra-blocks are coded using the second prediction modes that are thus determined. In particular, prediction errors that are assigned to the first intra-blocks are taken into consideration for the determination of the second prediction modes.

Abstract: Detecting a change between images is performed more effectively when a measure of change is used for the detection that depends on a length of the code blocks to which the images are individually entropy-encoded, and which are allocated to different sections of the respective image, since the length of these code blocks is also available without decoding. This uses the fact that the length or amount of data of a code block directly depends, in large parts, on the entropy and hence on the complexity of the allocated image section, and that changes between images are, with high probability, also reflected in a change of complexity.

Abstract: In uniform superposition of two predictions toward a weighted superposition, such as in coding B frames, weighting is based on reliability of a reference picture used for determination of the prediction. Since there is a relationship between the reliability and the respective quantization parameter, coupling to the quantization parameter that is also known in the receiver also can be effected advantageously.

Abstract: A method and a system for spatial scalable region of interest transcoding of JPEG2000 coded video frames for video surveillance systems are shown. Based on a user defined ROI the method transcodes HD frames into images in moderate resolution with a ROI in HD resolution. The transcoder extracts all packets belonging to the ROI or the lower resolution levels of the background from the JPEG2000 bitstream. Non-ROI packets of higher resolution levels are replaced by empty packets. The ROI is tracked using a mean shift algorithm to guarantee that always the correct image details are extracted in high resolution. Since the transcoding is performed by extracting and replacing packets of the codestream, an expensive re-encoding of the code-stream is not required. Thus, the transcoding technique is of low complexity and shows a short processing time. Combining the transcoding technique with mean shift tracking leads to a powerful video transcoding technique.

Abstract: Where a quantized data value is produced by a first quantization of an input data value, followed by a first inverse quantization and subsequently by a second quantization and the first quantization has first quantization intervals and the second quantization has second quantization intervals, third quantization intervals are generated by displacing interval boundaries of the second quantization intervals, respectively, to the next interval boundaries of the first quantization intervals. A third reconstruction value is determined for the third quantization intervals such that the third reconstruction value lies within the associated third quantization intervals. A corrected data value is generated by a third inverse quantization of the quantized data value and the third inverse quantization is affirmed by the third quantization intervals containing the associated third reconstruction value.

Abstract: In uniform superposition of two predictions toward a weighted superposition, such as in coding B frames, weighting is based on reliability of a reference picture used for determination of the prediction. Since there is a relationship between the reliability and the respective quantization parameter, coupling to the quantization parameter that is also known in the receiver also can be effected advantageously.

Abstract: The invention relates to a medical imaging system having a generation apparatus for continuous image data from successive examination images, having an encoding apparatus for the image data for the purpose of compression on the basis of the method of prediction, having an evaluation apparatus for physiological, periodic data for the purpose of determining the repetition rate thereof, and having a memory apparatus for the compressed image data, where the encoding apparatus is connected to the evaluation apparatus, which controls the latter such that the prediction is matched dynamically to the period length of the physiological data. The use of the information from the ECG signal, for example, for the purpose of compressing the original material provides a dynamic frame rate and also the opportunity to control the dependencies of the prediction such that a minimal memory requirement is obtained without loss of data.

Abstract: In uniform superposition of two predictions toward a weighted superposition, such as in coding B frames, weighting is based on reliability of a reference picture used for determination of the prediction. Since there is a relationship between the reliability and the respective quantization parameter, coupling to the quantization parameter that is also known in the receiver also can be effected advantageously.

Abstract: For an edge image block, the DC part of the encoding information of the picture elements contained in the edge image block is separately determined and is subtracted from the encoding information of the picture elements of the edge image block, as a result whereof an enhanced coding efficiency is achieved.

Abstract: An input data stream coded using a first coding method and containing at least one coded digitized image is converted into an output data stream that is coded using a second coding method. The input data stream has first intra-blocks, each of which is coded in a first prediction mode of a plurality of first intra-prediction modes, and the output data stream has second intra-blocks, each of which is coded in a second prediction mode of a plurality of second intra-protection modes. The second prediction modes of one or more second intra-blocks are determined with the aid of the first prediction modes for one or more first intra-blocks and the second intra-blocks are coded using the second prediction modes that are thus determined. In particular, prediction errors that are assigned to the first intra-blocks are taken into consideration for the determination of the second prediction modes.

Abstract: The invention relates to a medical imaging system having a generation apparatus for continuous image data from successive examination images, having an encoding apparatus for the image data for the purpose of compression on the basis of the method of prediction, having an evaluation apparatus for physiological, periodic data for the purpose of determining the repetition rate thereof, and having a memory apparatus for the compressed image data, where the encoding apparatus is connected to the evaluation apparatus, which controls the latter such that the prediction is matched dynamically to the period length of the physiological data. The use of the information from the ECG signal, for example, for the purpose of compressing the original material provides a dynamic frame rate and also the opportunity to control the dependencies of the prediction such that a minimal memory requirement is obtained without loss of data.

Abstract: A method for transmitting a vector having at least two vector components, each of the vector components described in a frequency. Each vector is represented as a bit number with a predetermined number of bit levels. The bit numbers are encoded according to a priority of the bit levels and the encoded bit numbers are transmitted.

Abstract: A method and a communication system are in which a first synchronization message identifying a data transmission method with the highest-level error protection that a first device is capable of executing is transmitted from said first device to a second device. In the second device, the data transmission method is detected from the first synchronization message. In case the detected data transmission method is supported by the second device, a second synchronization message is sent to the first device identifying the detected data transmission method. In the first device, the data transmission method is detected from the second synchronization message, and in case the detected data transmission method can be executed by the first device, the devices are synchronized with the data transmission method.