5 research outputs found
Codeur vidéo scalable haute-fidélité SHVC modulable et parallèle
After entering the digital era, video consumption evolved and defined new trends. Video contents can now be accessed with many platforms (television, computer, tablet, smartphones ... ) and from many medias such as mobile network or satellite network or terrestrial network or Internet or local storage on Blu-ray disc for instance. In the meantime, users experience improves thanks to new video format such as Ultra High Definition (UHD) or High Dynamic Range (HOR) or High Frame Rate (HFR). These formats respectively enhance quality through resolution, dynamic range and frequency. New consumption trends and new video formats define new constraints that have to be resolved by currents and futures video encoders. In this context, we propose a video coding solution able to answer constraints such as multi-formats coding, multiÂdestinations coding, coding speed and coding efficiency in terms of video compression. This solution relies on the scalable extension of the standard « High Efficiency Video Coding » (HEVC) defined in 2014 also called SHVC. This extension enables scalable video coding by producing a single bitstream on several layers built from a common video at different scales of resolution, frequency, quality, bit depth per pixel or even colour gamut. SHVC coding enhance HEVC coding thanks to an inter-layer prediction that use coding information from lower layers. In this PhD thesis, the proposed solution is based on a professional video encoder, developed by Ateme company, able to perform parallelism on several levels (inter-frames, intra-frames, inter-blocks, inter-operations) thanks to a pipelined architecture. Two instances of this encoder run in parallel and are synchronised at pipeline level to enable inter-layer predictions. Some trade-off between complexity and coding efficiency are proposed on inter-layer prediction at slice and prediction tools levels. For instance, in a broadcast configuration, inter-layer prediction is processed on reconstructed pictures only for half the frames of the bitstream. In a constant quality configuration, it enables to save 18.5% of the coding bitrate for only 2% loss in terms of coding speed compared to equivalent HEVC coding. The proposed architecture is also able to perform all kinds of scalability supported in the SHVC extension. Moreover, in spatial scalability, we propose a down-sampling filter processed on the base layer that optimized global coding bitrate. We propose several quality modes with parallelism on several levels and low-level optimization that enable real-time video coding on UHD sequences. The proposed solution was integrated in a video broadcast chain and showed in several professional shows, conferences and at ATSC 3.0 meetings.Après l'entrĂ©e dans l'ère du numĂ©rique, la consommation vidĂ©o a Ă©voluĂ© dĂ©finissant de nouvelles tendances. Les contenus vidĂ©o sont dĂ©sormais accessibles sur de nombreuses plateformes (tĂ©lĂ©vision, ordinateur, tablette, smartphone ... ) et par de nombreux moyens, comme les rĂ©seaux mobiles, les rĂ©seaux satellites, les rĂ©seaux terrestres, Internet ou le stockage Blu-ray par exemple. Parallèlement, l'expĂ©rience utilisateur s'amĂ©liore grâce Ă la dĂ©finition de nouveaux formats comme l'Ultra Haute DĂ©finition (UHD), le « High Dynamic Range » (HDR) ou le « High Frame Rate » (HFR). Ces formats considèrent une augmentation respectivement de la rĂ©solution, de la dynamique des couleurs et de la frĂ©quence d'image. Les nouvelles tendances de consommation et les amĂ©liorations des formats imposent de nouvelles contraintes auxquelles doivent rĂ©pondre les codeurs vidĂ©o actuels et futurs. Dans ce contexte, nous proposons une solution de codage vidĂ©o permettant de rĂ©pondre Ă des contraintes de codage multi-formats, multi-destinations, rapide et efficace en termes de compression. Cette solution s'appuie sur l'extension Scalable du standard de compression vidĂ©o « High Efficiency Video Coding » (HEVC) dĂ©finie en fin d'annĂ©e 2014, aussi appelĂ©e SHVC. Elle permet de rĂ©aliser des codages scalables en produisant un unique bitstream Ă partir d'un codage sur plusieurs couches construites Ă partir d'une mĂŞme vidĂ©o Ă diffĂ©rentes Ă©chelles de rĂ©solutions, frĂ©quences, niveaux de qualitĂ©, profondeurs des pixels ou espaces de couleur. Le codage SHVC amĂ©liore l'efficacitĂ© du codage HEVC grâce Ă une prĂ©diction inter-couches qui consistent Ă employer les informations de codage issues des couches les plus basses. La solution proposĂ©e dans cette thèse s'appuie sur un codeur HEVC professionnel dĂ©veloppĂ© par la sociĂ©tĂ© Ateme qui intègre plusieurs niveaux de parallĂ©lisme (inter-images, intra-images, inter-blocs et inter-opĂ©rations) grâce Ă une architecture en pipeline. Deux instances parallèles de ce codeur sont synchronisĂ©es via un dĂ©calage inter-pipelines afin de rĂ©aliser une prĂ©diction inter-couches. Des compromis entre complexitĂ© et efficacitĂ© de codage sont effectuĂ©s au sein de cette prĂ©diction au niveau des types d'image et des outils de prĂ©diction. Dans un cadre de diffusion, par exemple, la prĂ©diction inter-couches est effectuĂ©e sur les textures pour une image sur deux. A qualitĂ© constante, ceci permet d'Ă©conomiser 18.5% du dĂ©bit pour une perte de seulement 2% de la vitesse par rapport Ă un codage HEVC. L'architecture employĂ©e permet alors de rĂ©aliser tous les types de scalabilitĂ© supportĂ©s par l'extension SHVC. De plus, pour une scalabilitĂ© en rĂ©solution, nous proposons un filtre de sous-Ă©chantillonnage, effectuĂ© sur la couche de base, qui optimise le coĂ»t en dĂ©bit global. Nous proposons des modes de qualitĂ© intĂ©grant plusieurs niveaux de parallĂ©lisme et optimisations Ă bas niveau qui permettent de rĂ©aliser des codages en temps-rĂ©el sur des formats UHD. La solution proposĂ©e a Ă©tĂ© intĂ©grĂ©e dans une chaĂ®ne de diffusion vidĂ©o temps-rĂ©el et montrĂ©e lors de plusieurs salons, confĂ©rences et meetinqs ATSC 3.0
Modulr and parallel scalable high efficiency SHVC video encoder
Après l'entrĂ©e dans l'ère du numĂ©rique, la consommation vidĂ©o a Ă©voluĂ© dĂ©finissant de nouvelles tendances. Les contenus vidĂ©o sont dĂ©sormais accessibles sur de nombreuses plateformes (tĂ©lĂ©vision, ordinateur, tablette, smartphone ... ) et par de nombreux moyens, comme les rĂ©seaux mobiles, les rĂ©seaux satellites, les rĂ©seaux terrestres, Internet ou le stockage Blu-ray par exemple. Parallèlement, l'expĂ©rience utilisateur s'amĂ©liore grâce Ă la dĂ©finition de nouveaux formats comme l'Ultra Haute DĂ©finition (UHD), le « High Dynamic Range » (HDR) ou le « High Frame Rate » (HFR). Ces formats considèrent une augmentation respectivement de la rĂ©solution, de la dynamique des couleurs et de la frĂ©quence d'image. Les nouvelles tendances de consommation et les amĂ©liorations des formats imposent de nouvelles contraintes auxquelles doivent rĂ©pondre les codeurs vidĂ©o actuels et futurs. Dans ce contexte, nous proposons une solution de codage vidĂ©o permettant de rĂ©pondre Ă des contraintes de codage multi-formats, multi-destinations, rapide et efficace en termes de compression. Cette solution s'appuie sur l'extension Scalable du standard de compression vidĂ©o « High Efficiency Video Coding » (HEVC) dĂ©finie en fin d'annĂ©e 2014, aussi appelĂ©e SHVC. Elle permet de rĂ©aliser des codages scalables en produisant un unique bitstream Ă partir d'un codage sur plusieurs couches construites Ă partir d'une mĂŞme vidĂ©o Ă diffĂ©rentes Ă©chelles de rĂ©solutions, frĂ©quences, niveaux de qualitĂ©, profondeurs des pixels ou espaces de couleur. Le codage SHVC amĂ©liore l'efficacitĂ© du codage HEVC grâce Ă une prĂ©diction inter-couches qui consistent Ă employer les informations de codage issues des couches les plus basses. La solution proposĂ©e dans cette thèse s'appuie sur un codeur HEVC professionnel dĂ©veloppĂ© par la sociĂ©tĂ© Ateme qui intègre plusieurs niveaux de parallĂ©lisme (inter-images, intra-images, inter-blocs et inter-opĂ©rations) grâce Ă une architecture en pipeline. Deux instances parallèles de ce codeur sont synchronisĂ©es via un dĂ©calage inter-pipelines afin de rĂ©aliser une prĂ©diction inter-couches. Des compromis entre complexitĂ© et efficacitĂ© de codage sont effectuĂ©s au sein de cette prĂ©diction au niveau des types d'image et des outils de prĂ©diction. Dans un cadre de diffusion, par exemple, la prĂ©diction inter-couches est effectuĂ©e sur les textures pour une image sur deux. A qualitĂ© constante, ceci permet d'Ă©conomiser 18.5% du dĂ©bit pour une perte de seulement 2% de la vitesse par rapport Ă un codage HEVC. L'architecture employĂ©e permet alors de rĂ©aliser tous les types de scalabilitĂ© supportĂ©s par l'extension SHVC. De plus, pour une scalabilitĂ© en rĂ©solution, nous proposons un filtre de sous-Ă©chantillonnage, effectuĂ© sur la couche de base, qui optimise le coĂ»t en dĂ©bit global. Nous proposons des modes de qualitĂ© intĂ©grant plusieurs niveaux de parallĂ©lisme et optimisations Ă bas niveau qui permettent de rĂ©aliser des codages en temps-rĂ©el sur des formats UHD. La solution proposĂ©e a Ă©tĂ© intĂ©grĂ©e dans une chaĂ®ne de diffusion vidĂ©o temps-rĂ©el et montrĂ©e lors de plusieurs salons, confĂ©rences et meetinqs ATSC 3.0.After entering the digital era, video consumption evolved and defined new trends. Video contents can now be accessed with many platforms (television, computer, tablet, smartphones ... ) and from many medias such as mobile network or satellite network or terrestrial network or Internet or local storage on Blu-ray disc for instance. In the meantime, users experience improves thanks to new video format such as Ultra High Definition (UHD) or High Dynamic Range (HOR) or High Frame Rate (HFR). These formats respectively enhance quality through resolution, dynamic range and frequency. New consumption trends and new video formats define new constraints that have to be resolved by currents and futures video encoders. In this context, we propose a video coding solution able to answer constraints such as multi-formats coding, multiÂdestinations coding, coding speed and coding efficiency in terms of video compression. This solution relies on the scalable extension of the standard « High Efficiency Video Coding » (HEVC) defined in 2014 also called SHVC. This extension enables scalable video coding by producing a single bitstream on several layers built from a common video at different scales of resolution, frequency, quality, bit depth per pixel or even colour gamut. SHVC coding enhance HEVC coding thanks to an inter-layer prediction that use coding information from lower layers. In this PhD thesis, the proposed solution is based on a professional video encoder, developed by Ateme company, able to perform parallelism on several levels (inter-frames, intra-frames, inter-blocks, inter-operations) thanks to a pipelined architecture. Two instances of this encoder run in parallel and are synchronised at pipeline level to enable inter-layer predictions. Some trade-off between complexity and coding efficiency are proposed on inter-layer prediction at slice and prediction tools levels. For instance, in a broadcast configuration, inter-layer prediction is processed on reconstructed pictures only for half the frames of the bitstream. In a constant quality configuration, it enables to save 18.5% of the coding bitrate for only 2% loss in terms of coding speed compared to equivalent HEVC coding. The proposed architecture is also able to perform all kinds of scalability supported in the SHVC extension. Moreover, in spatial scalability, we propose a down-sampling filter processed on the base layer that optimized global coding bitrate. We propose several quality modes with parallelism on several levels and low-level optimization that enable real-time video coding on UHD sequences. The proposed solution was integrated in a video broadcast chain and showed in several professional shows, conferences and at ATSC 3.0 meetings
Efficient parallel architecture for a real-time UHD scalable HEVC encoder
International audienc
4K Real Time Software Solution of Scalable HEVC for Broadcast Video Application
International audienceScalable High efficiency Video Coding (SHVC) is the scalable extension of the High Efficiency Video Coding (HEVC) standard. SHVC enables spatial, quality, bit-depth, color gamut and codec scalability. The architecture of the SHVC encoder is based on multiple instances of the HEVC encoder where each instance encodes one video layer. This architecture offers several advantages of being modular and close to the native HEVC coding block scheme. However, the close-loop SHVC architecture requires the complete decoding of the reference lower-layer frames to decode a higher quality layer, which considerably increases the complexity of both encoder and decoder processes. In this paper, we propose an end-to-end 4K real time SHVC solution, including both software encoder and decoder, for video broadcast applications. The SHVC codec relies on low level optimizations for specific Intel x86 platform and parallel processing to speed-up the encoding and decoding processes. The proposed encoder enables a real time processing of 4Kp30 video in 2x spatial scalability on the 4x10-cores Intel Xeon processor (E5-4627V3) running at 2.6 GHz. In addition, the SHVC decoder enables to decode, respectively, the lower quality layer in full HD (1920x1080p30) resolution, on ARM Neon mobile platform, and the enhancement layer in UHD (3840x2160p30), on a laptop fitted, with 4 cores Intel i7 processor running at 2.7 GHz. Finally, experimental results have shown that the proposed solution can reach a high rate-distortion performance close to the reference SHVC reference software Model (SHM) with a speed-up of 37 and 66 in Intra and Inter coding configurations