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Showing papers on "Alpha compositing published in 2015"


Patent
Eric Christensen1, Marc Hanson1
20 Apr 2015
TL;DR: In this paper, a common alpha channel value is applied to pixels in a decompressed image representation correlated to the at least one common type pixel run in the encoded alpha channel data.
Abstract: Techniques for a compressed image with alpha channel data are described. Encoded alpha channel data from a compressed image representation may be extracted. A common type pixel run characteristic may be determined for at least one common type pixel run represented in the encoded alpha channel data. A common alpha channel value is applied, based on the common type pixel run characteristic, to pixels in a decompressed image representation correlated to the at least one common type pixel run. Pixels in the decompressed image representation correlating to at least one lookup type pixel run represented in the encoded alpha channel data may be processed. The processing may include a determination of an alpha channel value based on pixel data, specific to a pixel correlated to the lookup type pixel run, in the encoded alpha channel data and an application of the alpha channel value to the pixel.

18 citations


Proceedings ArticleDOI
08 Aug 2015
TL;DR: An improved method of producing and manipulating deep pixel data which retains important surface information calculated during the execution of the rendering algorithm for later use during compositing, allowing operations normally performed in the renderer to be deferred until compositing.
Abstract: We present an improved method of producing and manipulating deep pixel data which retains important surface information calculated during the execution of the rendering algorithm for later use during compositing, allowing operations normally performed in the renderer to be deferred until compositing. These include pixel-coverage calculation, pixel filtering, hard-surface blending, and matte object handling. Current methodologies for representing and transmitting deep pixel data work well for combining volumetric and hard-surface renders but are not very successful at combining hard-surfaces. By retaining additional surface information a renderer's final integration steps can be reconstructed later in compositing.

10 citations


Patent
Xiaocheng Marc Mao1, Yi Yang
25 Dec 2015
TL;DR: In this paper, a graphics processing engine is configured to render pixel data to a tile of memory and write to metadata associated with the tile that indicates a data characteristic of the pixel data.
Abstract: Embodiments provide for a graphics processing apparatus comprising a graphics processing engine configured for tiled memory access. In one embodiment the graphics processing engine is configured to render pixel data to a tile of memory and write to metadata associated with the tile of memory that indicates a data characteristic of the pixel data. The data characteristic of the pixel data includes whether the pixel data is transparent or whether the pixel data is an update of data from a previous frame.

7 citations


01 Jan 2015
TL;DR: The panoramic video system is designed as a vehicle mounted system, but can be applied to several other areas, such as surveillance, and is capable of processing about 15 frames per second making it close to real-time.
Abstract: In this thesis a system for creating panoramic video has been developed. The panoramic video is formed by stitching several camera streams together. The system is designed as a vehicle mounted system, but can be applied to several other areas, such as surveillance. The system creates the video by finding features that correspond in the overlapping frames. By using cylinder projection the problem is reduced to finding a translation between the images and using algorithms such as ORB matching features can be detected and described. The camera frames are stitched together by calculating the average translation of the matching features. To reduce artifacts such as ghosting, a simple but effective alpha blending technique has been used. The system has been implemented using C++ and the OpenCV library and the algorithm is capable of processing about 15 frames per second making it close to real-time. With future improvements, such as parallel processing of the cameras, the system may be speeded up even further and possibly include other types of image processing, e.g. object recognition and tracking.

5 citations


Patent
26 Oct 2015
TL;DR: This article converted an image into a transparency, or "foreground image layer", on which the readability of text and other detail is preserved after compositing with a background, while maintaining color information of broad areas of the image.
Abstract: The present invention converts an image into a transparency, or “foreground image layer”, on which the readability of text and other detail is preserved after compositing with a background, while maintaining color information of broad areas of the image. In an embodiment, a matte is determined for the background image to reduce transparencies in the foreground layer, so as to prevent irrelevant parts of the background image from showing through. This is in distinction to only using the original foreground image data (prior to its transformation to a layer) to compute a matte (or mask, or alpha channel) to form a foreground layer.

5 citations


Patent
18 Feb 2015
TL;DR: In this article, an image generating method and device is described, which includes: acquiring contents inserted into a video; generating the PNG-format data of to-be-generated images according to the contents; and generating the BMP-format images inserted to the video according to a PNG format data.
Abstract: The invention discloses an image generating method and device. The method includes: acquiring contents inserted into a video; generating the PNG-format data of to-be-generated images according to the contents, wherein the PNG-format data includes the alpha channel data of the to-be-generated images; generating the BMP-format images inserted to the video according to the PNG-format data.

3 citations


Patent
Teruyuki Higashiyama1
05 Jun 2015
TL;DR: In this paper, an image processing apparatus includes a detection unit configured to detect a blur of an image-capturing apparatus, a change in a subject brightness, or a color of a subject.
Abstract: An image processing apparatus includes a detection unit configured to detect a blur of an image-capturing apparatus, a change in a subject brightness, or a change in a color of a subject, an image-capturing control unit configured to perform control so that the image-capturing apparatus performs image-capturing a plurality of times in accordance with a single image-capturing command, a composite unit configured to composite a plurality of images captured in accordance with the single image-capturing command, and a control unit configured such that when the control unit obtains information indicating that a predetermined blur, a change in a predetermined subject brightness, or a change in a color of a predetermined subject is detected based on a detection result, the control unit controls the composite unit so as to generate a composition image made by compositing a plurality of images captured before the detection.

3 citations


Proceedings ArticleDOI
26 Feb 2015
TL;DR: In this paper, a matrix barcode with the three level image watermarking using QR code and digital signature to verify image copyrights is proposed and the alpha channel is used for controlling the transparency of the image.
Abstract: Based on the increased awareness towards digital rights in commercial activity, the internet and media demands protection to enhance security. In this paper, predicated level of reversible watermarking scheme for image integrity and tamper detection or localization aspect. The proposed integrity analysis process is based on the region of interest watermarking with signatures and the use of alpha channel. Also integrity is analyzed at three distinct levels, which are used for the detection of modification, modified location and forensic analysis respectively. Behind this a digital watermark with 2D Barcode is a widely interesting research in the security field. Here this paper proposes a matrix barcode with the three level image watermarking using QR code and digital signature to verify image copyrights. A new watermarking method via the use of alpha channel is proposed. The alpha channel is used for controlling the transparency of the image. In proposed watermarking framework, it allows a user with an appropriate hash function SHA to verify the authenticity, integrity a ownership of an image. It is used as a metric in localization of tampered regions. The schemes successfully localize attack. The analysis scheme has shows high fidelity and is capable of localizing modified regions in watermarked image or localization of tampering. Mainly the channel watermarking can added to make system more robust to detect tampering attacks. Sole Purpose is to verify the integrity i.e. tamper verification.

3 citations


Patent
20 Feb 2015
TL;DR: In this paper, an example method of displaying data on a display device includes computing a texture based on a difference between a high quality (HQ) tile and a corresponding low quality (LQ) tile.
Abstract: Systems and methods are disclosed for displaying data on a display device. An example method of displaying data on a display device includes computing a texture based on a difference between a high quality (HQ) tile and a corresponding low quality (LQ) tile. The method also includes storing the texture into an alpha channel of the LQ tile. The method further includes compositing the LQ tile onto the display device when an attribute of the alpha channel satisfies a threshold.

3 citations


01 Jan 2015
TL;DR: This paper proposed steganography based on alpha channel, the art and science of communicating in such a way that the presence of a message cannot be detected.
Abstract: Steganography is the art or practice of concealing a message, image, or file within another message, image, or file. It is the art and science of communicating in such a way that the presence of a message cannot be detected. Generally, the hidden messages will appear to be (or be part of) something else: images, articles, shopping lists, or some other cover text. For example, the hidden message may be in invisible ink between the visible lines of a private letter. In this paper we proposed steganography based on alpha channel.

2 citations


Proceedings ArticleDOI
31 Jul 2015
TL;DR: K Kubelka-Munk model (KM model in short) simulates pigment compositing as well as paint-like appearance by physically-based simulation, but it is difficult to use KM model because of many simulation parameters.
Abstract: Many people have been familiar with subtractive color model based on pigment color compositing since their early childhood. However, the RGB color space is not comprehensible for children due to additive color compositing. In the RGB color space, the resulting mixture color is often different from colors viewer expected. CMYK is a well-known subtractive color space, but its three primal colors are not familiar. Kubelka-Munk model (KM model in short) simulates pigment compositing as well as paint-like appearance by physically-based simulation. However, it is difficult to use KM model because of many simulation parameters.

Proceedings ArticleDOI
01 Nov 2015
TL;DR: This paper focuses on alpha blending using selector logics and implement it on an FPGA board, which realizes approximately 23% speed-up and 8% area reduction simultaneously using selector-logic based alpha blending.
Abstract: Alpha blending is one of image synthesis techniques, which synthesizes a new image by summing up weighted input images and realizes transparent effect. In this paper, we focus on alpha blending using selector logics and implement it on an FPGA board. By applying selector logics to the alpha blending operation, its total product terms are decreased and thus a circuit size and circuit delay are improved simultaneously. In our implementation, original pixel values are stored into a memory on the FPGA board and then a new pixel value is synthesized based on input transmittance factors. We realize approximately 23% speed-up and 8% area reduction simultaneously using selector-logic based alpha blending.

Journal Article
TL;DR: A method has been proposed using which a large size secret image can be hidden into small size of cover image securely, achieving the absolute invisibility of the large sizesecret image.
Abstract: In this paper, a method has been proposed using which a large size secret image (containing hidden encrypted message) can be hidden into small size of cover image securely. The main aim here is the absolute invisibility of the large size secret image. The proposed method does not require the sender to send the cover image to the receiver for obtaining the secret image.

01 Jan 2015
TL;DR: The system which is proposed will first encrypt the confidential data to be transmitted by using the AES algorithm and then this encrypted data is encapsulated into an image which acts as a cover image which is digital watermarked to protect the authenticity of the data.
Abstract: In this paper, we are proposing a tactic to provide secure confidential data transmission through the internet which has revolutionized the mode of transmitting data. To achieve this we are using AES algorithm and BPCS steganography technique. The system which we are proposing will first encrypt the confidential data to be transmitted by using the AES algorithm and then this encrypted data is encapsulated into an image which acts as a cover image. For encapsulating the encrypted data into the image BPCS steganography is used which has the reputation of providing large data embedding capacity and preventing the degradation of the quality of the stego image. And now finally this stego image is encrypted by using AES algorithm thereby providing twofold protection to the confidential data and thus overcoming the shortcomings of the previous researchers. So at the sender side two keys are generated i.e. a data encryption key and an image encryption key. Now lastly at the sender side as an add-on feature the encrypted stego image is digital watermarked to protect the authenticity of the data. Now this final encrypted stego image is sent to the receiver and the receiver would be able to extort the encrypted data from the encrypted image and then would decrypt the encrypted stego image with the image encryption key. And then finally with the help of the data encryption key the receiver will decrypt the encrypted data. Hence same set of keys are used for encryption as well as for decryption and as two separate keys are used for encrypting the data and the image, the process of decryption is separable as well as reversible due to the use of AES algorithm. Keywords— Cryptography, Steganography, BPCS (Bit Plane Complexity Segmentation), AES (Advanced Encryption Standard), alpha channel, Digital Watermarking , TGA(Truevision Graphics Adapter). Shruti Gajare et al, International Journal of Computer Science and Mobile Computing, Vol.4 Issue.3, March2015, pg. 396-405 © 2015, IJCSMC All Rights Reserved 397

Patent
19 Nov 2015
TL;DR: In this article, a difference image between a base target and a swap target after aligned is generated, and an extracted contour in the difference image is determined in accordance with an active contour model.
Abstract: PROBLEM TO BE SOLVED: To generate a desired synthesized image into which a moving area of a subject is synthesized appropriatelySOLUTION: A difference image between a base target and a swap target after aligned is generated (S1021), and an extracted contour in the difference image is determined in accordance with an active contour model (S1022) An inner area of the contour and an outer area of the contour are painted with different colors so as to generate a mask image for alpha blending (S1023) Using the mask image thus generated, the swap target that is aligned with respect to the base target is synthesized with the base target of a reference image by alpha blending (S1024)SELECTED DRAWING: Figure 6

Proceedings ArticleDOI
01 Oct 2015
TL;DR: This paper proposes a scene-adaptive color transfer model with an application for image compositing and introduces an adaptive source compositing region selection method and addresses the boundary transition by a discrete Poisson solver.
Abstract: Compositing is one of the most critical techniques in various aspects such as movie production and computer graphics When images have complex textures, existing color based methods require exhaustive training samples to achieve plausible compositing results In this paper, we propose a scene-adaptive color transfer model with an application for image compositing We extract foregrounds from the source and target images Then, we divide the source and target images into unequal bands according to the luminance After that, color transfer is conducted by dynamically adjusting the weights of luminance and chrominance To achieve a realistic composite, we introduce an adaptive source compositing region selection method and address the boundary transition by a discrete Poisson solver The experiment results illustrate that our method achieves a faithful color transfer In addition, our composite results appear highly realistic

Book ChapterDOI
11 Mar 2015
TL;DR: This research develops an application to execute matting process of a transparent object and compositing it into a new image by exploiting transparency value and object refraction.
Abstract: Nowadays, image manipulation, which is related to matting and compositing process, is commonly used. Processed object may vary, however matters may arise when the object is transparent. Not many research has been conducted about the issue due to the difficulties in extracting transparency value and object refraction. In this research an application to execute matting process of a transparent object and compositing it into a new image is developed.

Patent
09 Sep 2015
TL;DR: In this article, an image adjusting method and a device are used for positioning the background of an image at the same color level, and are beneficial for segmenting the foreground and background of the image.
Abstract: The present disclosure relates to an image adjusting method and a device, which are used for positioning the background of an image at the same color level, and are beneficial for segmenting the foreground and the background of the image. The method comprises: performing summation on the gray-scale value of set row number started from the first edge of an original image to obtain a first set of gray-scale sum value; performing summation on the gray-scale value of set row number started from the second edge, vertical to the first edge, of the original image to obtain a second set of gray-scale sum value; determining the composition angle between the first set of gray-scale sum value and the second set of gray-scale sum value; adjusting the alpha channel of the original image by the composition angle. The technical scheme disclosed by the invention enables a background image with approximate linear gray-scale change to recover to a background image positioned at the same color level, is beneficial for the segmentation of the foreground image and the background image of the original image, and avoids the situation that the bar graphs of the foreground image and the background image affect the thresholding before image feature extraction.

Journal Article
TL;DR: A new authentication method which is based on secret sharing technique with self repair capability, which takes color image then each block of that image genarate the authentication signal and applies the Shamir secret sharing method.
Abstract: In this paper we proposed a new authentication method which is based on secret sharing technique with self repair capability. In this paper, we take color image then each block of that image genarate the authentication signal. Then we apply the Shamir secret sharing method. In that method each block of image are transfered into several shares. Then we apply alpha channel plane for PNG image formation. After that that PNG image is encrypted using chaotic logistic map and forms the stego image. This stego image is received by the receiver. If the image is tampered then we used the Reverse Shamir secret algorithm and repair that tampered image and get the original image.

DOI
12 Sep 2015
TL;DR: DT based watermarking technique, the frames selected from a video is get decomposed through the DWT in 3-levels and watermark is embedded into the low frequency sub-band of a original frame by using alpha blending technique and the Arnold transform is one of the popular symmetric key as an encryption and decryption method.
Abstract: The growth of the Internet has frequently increased the availability of digital data such as text, audio, images and videos to the public. Digital watermarking is one of the important techniques to secure digital data in the field of authentication, copyright protection and security. The non-blind watermarking systems have a main problem that for extracting the watermark image from the watermarked image, the original image is required. Due to this it required more memory in both sender and receiver and double bandwidth in communications channel. In this paper a solution and more effective non-blind video watermarking depends on using image interlacing as a new way in the watermarking systems. In this paper DWT based watermarking technique, the frames selected from a video is get decomposed through the DWT in 3-levels and watermark is embedded into the low frequency sub-band of a original frame by using alpha blending technique and the Arnold transform is one of the popular symmetric key as an encryption and decryption method. The results obtained by these techniques are further compared and analyzed. Keyword: Reversible watermarking, interlacing and de-interlacing, non-blind, Arnold transform 3-level DWT and alpha blending.

Journal Article
TL;DR: Steganography is proposed that hides the very existence of the message in the communicating data in order to hide noise like shares generated as a result of encryption.
Abstract: Visual cryptography (VC) is a technique that encrypts secret image in meaningful images. The meaningful images can be photos or hand-painted pictures in digital form or in printed form. N such shares can be used. VC is used to securely transmit secret images in non-computer aided environment. The shares can appear as noise-like pixels it will arouse suspicion and increase interception risk during transmission of the shares. Hence, VC schemes suffer from a transmission risk problem for the secret image. We also propose possible ways to hide the noise like share to reduce the transmission risk problem for the share. Cryptography hides the contents of the message from an attacker, but not the existence of the message.To addresses this problem; we proposed Steganography that hides the very existence of the message in the communicating data. To hide noise like shares generated as a result of encryption, carrier image is used to reduce transmission risk; this technique used is called ‘Steganography’. In addition to this Alpha channel watermarking is used in case where hackers hack the image and try to destroy the image. In alpha channel water marking the average value of RGB of meaningful shares is stored in alpha channel. Such that receiver is able to make it out the integrity of received image by comparing original image with alpha channel embedded image.

01 Jan 2015
TL;DR: A new authentication method for binary like gray scale document images based on the secret sharing technique with a data repair capability via the use of the Portable Network Graphics (PNG) image is proposed.
Abstract: Digital image authentication is difficult for binary images because of its simple binary nature which leads to visible changes after authentication signals are embedded in the image pixels. Hence effective solution to ensure authentication of binary images should take in to account not only security issue of preventing image tampering but also keeping visual quality of resulting image. A new authentication method for binary like gray scale document images based on the secret sharing technique with a data repair capability via the use of the Portable Network Graphics (PNG) image is proposed. An authentication signal is generated for each block of a gray scale document image, which together with the binaries image block content, is transformed into several shares using the Shamir secret sharing scheme and then these shares are embedded into an alpha channel plane. Alpha channel plane is transparent plane; this plane is then combined with the original gray scale image to form stego image in PNG format. In the process of image authentication and verification, an image block is marked as tampered if the authentication signal computed from the current image block content does not match with shares extracted which are embedded in the alpha channel plane. Data repairing is then applied to each tampered image block by a reverse Shamir scheme after collecting two shares from unmarked blocks. Measures for protecting the security of the image content hidden in the alpha channel plane are also proposed.

01 Jan 2015
TL;DR: A visionless authentication method based on secret sharing technique with additional data repairing ability for the gray-scale document images by using Portable Network Graphics (PNG) is presented and can survive malicious attacks of common content modification.
Abstract: A visionless authentication method is based on secret sharing technique with additional data repairing ability for the gray-scale document images by using Portable Network Graphics (PNG) is presented. For each data block of gray-scale document images authentication signal is produced then this produced authentication signal and binarized data block content is transmute by using the secret Shamir scheme ,the contributed values are selected such that as many shares can produced and place in to the alpha channel plane. To create PNG image the alpha channel plane is added with the gray-scale document image at the time of placing the values, computed shares are correlated to the range of alpha channel values extent up to 255 to get the stego-image. An image block is patent as damaged if the authentication signal calculated from the present block that does not matches which is calculated from the placed values of alpha channel plane. The reverse Shamir scheme is applied to repair the damaged data block content by collecting two shares from unobtrusive data block. The proposed method can survive malicious attacks of common content modification, such as super imposition, painting etc.

01 Jun 2015
TL;DR: The proposed algorithm use principal component analysis (PCA) and k-nearest neighborhood (k-NN) to determine the location of input images before performing a template-based matching and synthesize input images by alpha blending to improve the computational efficiency.
Abstract: Image stitching method is a technique for obtaining an high-resolution image by combining two or more images. In X-ray image for clinical diagnosis, the size of the imaging region taken by one shot is limited due to the field-of-view of the equipment. Therefore, in order to obtain a high-resolution image including large regions such as a whole body, the synthesis of multiple X-ray images is required. In this paper, we propose a rapid stitching method of digital X-ray images using template-based registration. The proposed algorithm use principal component analysis(PCA) and k-nearest neighborhood(k-NN) to determine the location of input images before performing a template-based matching. After detecting the overlapping position using template-based matching, we synthesize input images by alpha blending. To improve the computational efficiency, reduced images are used for PCA and k-NN analysis. Experimental results showed that our method was more accurate comparing with the previous method with the improvement of the registration speed. Our stitching method could be usefully applied into the stitching of 2D or 3D multiple images.