Recherche avancée

Médias (16)

Mot : - Tags -/mp3

Autres articles (57)

  • Contribute to documentation

    13 avril 2011

    Documentation is vital to the development of improved technical capabilities.
    MediaSPIP welcomes documentation by users as well as developers - including : critique of existing features and functions articles contributed by developers, administrators, content producers and editors screenshots to illustrate the above translations of existing documentation into other languages
    To contribute, register to the project users’ mailing (...)

  • Ajouter notes et légendes aux images

    7 février 2011, par

    Pour pouvoir ajouter notes et légendes aux images, la première étape est d’installer le plugin "Légendes".
    Une fois le plugin activé, vous pouvez le configurer dans l’espace de configuration afin de modifier les droits de création / modification et de suppression des notes. Par défaut seuls les administrateurs du site peuvent ajouter des notes aux images.
    Modification lors de l’ajout d’un média
    Lors de l’ajout d’un média de type "image" un nouveau bouton apparait au dessus de la prévisualisation (...)

  • Encoding and processing into web-friendly formats

    13 avril 2011, par

    MediaSPIP automatically converts uploaded files to internet-compatible formats.
    Video files are encoded in MP4, Ogv and WebM (supported by HTML5) and MP4 (supported by Flash).
    Audio files are encoded in MP3 and Ogg (supported by HTML5) and MP3 (supported by Flash).
    Where possible, text is analyzed in order to retrieve the data needed for search engine detection, and then exported as a series of image files.
    All uploaded files are stored online in their original format, so you can (...)

Sur d’autres sites (9777)

  • libavutil : add an FFT & MDCT implementation

    2 mai 2019, par Lynne
    libavutil : add an FFT & MDCT implementation

    This commit adds a new API to libavutil to allow for arbitrary transformations
    
on various types of data.
    
This is a partly new implementation, with the power of two transforms taken
    
from libavcodec/fft_template, the 5 and 15-point FFT taken from mdct15, while
    
the 3-point FFT was written from scratch.
    
The (i)mdct folding code is taken from mdct15 as well, as the mdct_template
    
code was somewhat old, messy and not easy to separate.
    

    A notable feature of this implementation is that it allows for 3xM and 5xM
    
based transforms, where M is a power of two, e.g. 384, 640, 768, 1280, etc.
    
AC-4 uses 3xM transforms while Siren uses 5xM transforms, so the code will
    
allow for decoding of such streams.
    
A non-exaustive list of supported sizes :
    
4, 8, 12, 16, 20, 24, 32, 40, 48, 60, 64, 80, 96, 120, 128, 160, 192, 240,
    
256, 320, 384, 480, 512, 640, 768, 960, 1024, 1280, 1536, 1920, 2048, 2560...
    

    The API was designed such that it allows for not only 1D transforms but also
    
2D transforms of certain block sizes. This was partly on accident as the stride
    
argument is required for Opus MDCTs, but can be used in the context of a 2D
    
transform as well.
    
Also, various data types would be implemented eventually as well, such as
    
"double" and "int32_t".
    

    Some performance comparisons with libfftw3f (SIMD disabled for both) :
    
120 :
    
  22353 decicycles in     fftwf_execute,     1024 runs,      0 skips
    
  21836 decicycles in compound_fft_15x8,     1024 runs,      0 skips
    

    128 :
    
  22003 decicycles in       fftwf_execute,   1024 runs,      0 skips
    
  23132 decicycles in monolithic_fft_ptwo,   1024 runs,      0 skips
    

    384 :
    
  75939 decicycles in      fftwf_execute,    1024 runs,      0 skips
    
  73973 decicycles in compound_fft_3x128,    1024 runs,      0 skips
    

    640 :
    
 104354 decicycles in       fftwf_execute,   1024 runs,      0 skips
    
 149518 decicycles in compound_fft_5x128,    1024 runs,      0 skips
    

    768 :
    
 109323 decicycles in      fftwf_execute,    1024 runs,      0 skips
    
 164096 decicycles in compound_fft_3x256,    1024 runs,      0 skips
    

    960 :
    
 186210 decicycles in      fftwf_execute,    1024 runs,      0 skips
    
 215256 decicycles in compound_fft_15x64,    1024 runs,      0 skips
    

    1024 :
    
 163464 decicycles in       fftwf_execute,   1024 runs,      0 skips
    
 199686 decicycles in monolithic_fft_ptwo,   1024 runs,      0 skips
    

    With SIMD we should be faster than fftw for 15xM transforms as our fft15 SIMD
    
is around 2x faster than theirs, even if our ptwo SIMD is slightly slower.
    

    The goal is to remove the libavcodec/mdct15 code and deprecate the
    
libavcodec/avfft interface once aarch64 and x86 SIMD code has been ported.
    
New code throughout the project should use this API.
    

    The implementation passes fate when used in Opus, AAC and Vorbis, and the output
    
is identical with ATRAC9 as well.
    • [DH] libavutil/Makefile
    • [DH] libavutil/tx.c
    • [DH] libavutil/tx.h

  • avfilter/vf_vpp_qsv : add scale mode option

    24 février 2021, par Fei Wang
    avfilter/vf_vpp_qsv : add scale mode option

    The option allow user to set diffenent scaling mode from
    
auto/low-power/high-quality.
    

    More details :
    
https://github.com/Intel-Media-SDK/MediaSDK/blob/master/doc/mediasdk-man.md#mfxExtVPPScaling
    

    Signed-off-by : Fei Wang <fei.w.wang@intel.com>
    
Signed-off-by : Linjie Fu <linjie.justin.fu@gmail.com>
    • [DH] libavfilter/vf_vpp_qsv.c

  • avfilter/af_headphone : Remove pointless additions

    28 août 2020, par Andreas Rheinhardt
    avfilter/af_headphone : Remove pointless additions

    buffer_length is a power-of-two and modulo is buffer_length - 1, so that
    
buffer_length & modulo is zero.
    

    Reviewed-by : Paul B Mahol <onemda@gmail.com>
    
Signed-off-by : Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
    • [DH] libavfilter/af_headphone.c

Navigation