Fehmi Chebil

Efficient Algorithms for Editing H.263 and MPEG-4 Videos on Mobile Terminals

With the prevalence of hand-held devices equipped with digital cameras and capable of capturing long videos, there has been a substantial increase in the creation and availability of video content. Most of the video clips that are created are, however, unprofessional in quality. Video editing tools are used to fine-tune, clean and refine the captured video content. While such clips can be edited on PC, it is inconvenient tedious and sometimes impossible to transfer files between mobile device and PC. It is, therefore, more convenient for users to edit their videos on their mobile devices. On the other hand, with the constraints in processing power and memory in hand-held devices, spatial domain editing is not practical. However, compressed domain editing solutions can overcome such limitations. In this paper, we present efficient, compressed domain algorithms for video editing, which when tested on mobile devices, provide significant savings in computations compared to the conventional spatial domain approach.

Video and Audio Editing for Mobile Applications

Video content creation and consumption have been increasingly available for the masses with the emergence of handheld devices capable of shooting, downloading, and playing videos. Video editing is a natural and necessary operation that is most commonly employed by users for finalizing and organizing their video content. With the constraints in processing power and memory, conventional spatial domain video editing is not a solution for mobile applications. In this paper, we present a complete video editing system for efficiently editing video content on mobile phones using compressed domain editing algorithms. A critical factor from usability point of view is the processing speed of the editing application. We show that with the proposed compressed domain editing system, typical video editing operations can be performed much faster than real-time on todays S60 phones

Compressed domain editing of H.263 and MPEG-4 videos

Video content creation and production has reached the masses, as almost everyone is now able to create video dips on a daily basis. Video editing is a natural and necessary operation that is most commonly employed by users after video capture. Wireless imaging and video capturing devices, with hardware constraints of memory and processing power, are unable to accommodate conventional spatial domain video editing. In this paper we present a set of algorithms for efficiently performing editing effects on video content. The proposed algorithms, covering intra and inter sequence operations, are applied on H.263 and MPEG-4 compressed video sequences. The techniques ensure that the desired effects are achieved generating standard compliant codestreams, with significant savings in computations compared to the convention approach based on spatial domain editing.

A framework for image classification

Image annotation process requires time and human intervention. In this research we propose a framework to incrementally annotate images in the database based on user feedback. At the beginning users provide some annotations for images manually as a ground truth. Classifier is trained based on this ground truth. The classifier predicts annotation for new images that are not part of the ground truth. Feedback is collected from the users to increase the size of the training set and then the classifier is retrained. The system strives to capture feedback from users and retrains the classifier on the new training set. Our proposed framework facilitates semi-automatic image annotation

Compressed domain transcoding solutions for MPEG-4 visual simple profile and H.263 baseline videos in 3GPP services and applications

To provide basic video services and applications in 3G wireless networks, two video coding formats, H.263 baseline and MPEG-4 visual simple profile, are commonly adopted in different forms for various usage scenarios. To ensure interoperability between these cases, we propose efficient compressed domain algorithms for transcoding between MPEG-4 visual simple profile and H.263 baseline, and among MPEG-4 visual simple profile coding modes. Experimental results show that our suggested algorithms provide significant complexity reduction and quality improvement, in terms of PSNR, compared to the spatial domain approach. Being the first complete work on transcoding between all kinds of MPEG-4 visual simple profile and H.263 baseline bit streams, we believe this work provides valuable solutions for various 3GPP (3rd generation partnership project) compliant video services and applications).

Pre-compression rate allocation for JPEG2000 encoders in power constrained devices

The JPEG2000 coding scheme is slowly getting into use in imaging applications. The standard offers a set of new features and a better compression efficiency compared to the baseline JPEG. It requires, however, a high computational cost, making its usage in constrained devices, such as mobile phones or PDAs, challenging. We present a precompression rate allocation technique to reduce the encoding complexity and help adoption of JPEG2000 in such contexts.

Compressed domain editing of JPEG2000 images

To process or introduce editing effects on JPEG2000 images, we propose techniques applying these operations in the compressed domain. Our approach exploits the properties of the wavelet transform and the rich bitstream syntax of the JPEG2000 standard. The suggested techniques provide significant speed-ups compared to the conventional methods based on spatial domain processing of the decoded images.

Compressed Domain Video Editing

This paper addresses introduction of special video effects to the coded bitstreams in compressed domain. We propose novel compressed domain operations to achieve several video editing effects for motion-compensated family of video codecs. We then present detailed description of achieving blending of two video sequences. Results demonstrate significant computational savings over the conventional approach

JPEG 2000 for wireless applications

JPEG2000 is the new ISO/IEC image compression standard. It is a full coding system targeted for various imaging applications. Besides offering the state-of-the-art in still image compression, it provides new features such as scalability in quality and in resolution, random access and region of interest (ROI) coding. Motion JPEG2000 is an inherited video compression standard based on intra-farme coding using JPEG2000. JPIP (the JPEG2000 Interactive Protocol), is a developing protocol for the access and transmission of JPEG2000 coded data and related metadata in a networked environment. In this paper, we present various applications of JPEG2000, Motion JPEG2000 and JPIP, geared specially towards the wireless mobile environment. We present an Image Surfing system for surfing JPEG2000 images on mobile terminals over a wireless network. We also present a scheme for tracking and coding Regions-Of-Interest (ROI) over a Motion JPEG2000 sequence. Finally, we present a Partial Coding scheme for use in Motion JPEG2000 sequences that gives coding gains for certain types of video sequences.