ffmpeg-light-0.8.2: Minimal bindings to the FFmpeg library.

Safe HaskellNone
LanguageHaskell2010

Codec.FFmpeg

Contents

Description

Interface to initialize FFmpeg, decode video files, encode video files, and convert decoded image frames to JuicyPixels images.

Synopsis

Initialization

initFFmpeg :: IO () Source

Initialize FFmpeg by registering all known codecs. This must be called before using other FFmpeg functions.

Decoding

imageReader :: JuicyPixelFormat p => FilePath -> IO (IO (Maybe (Image p)), IO ()) Source

Read frames from a video stream. Errors are thrown as IOExceptions.

imageReaderTime :: JuicyPixelFormat p => FilePath -> IO (IO (Maybe (Image p, Double)), IO ()) Source

Read time stamped frames from a video stream. Time is given in seconds from the start of the stream. Errors are thrown as IOExceptions.

imageReaderT :: forall m p. (Functor m, MonadIO m, MonadError String m, JuicyPixelFormat p) => FilePath -> m (IO (Maybe (Image p)), IO ()) Source

Read frames from a video stream.

imageReaderTimeT :: forall m p. (Functor m, MonadIO m, MonadError String m, JuicyPixelFormat p) => FilePath -> m (IO (Maybe (Image p, Double)), IO ()) Source

Read time stamped frames from a video stream. Time is given in seconds from the start of the stream.

Encoding

data EncodingParams Source

Minimal parameters describing the desired video output.

Constructors

EncodingParams 

Fields

epWidth :: CInt
 
epHeight :: CInt
 
epFps :: Int
 
epCodec :: Maybe AVCodecID

If Nothing, then the codec is inferred from the output file name. If Just, then this codec is manually chosen.

epPixelFormat :: Maybe AVPixelFormat

If Nothing, automatically chose a pixel format based on the output codec. If Just, force the selected pixel format.

epPreset :: String

Encoder-specific hints. For h264, the default preset is "medium" (other options are "fast", "slow", etc.). For the GIF codec, setting this to "dither" will enable dithering during the palettization process. This will improve image quality, but result in a larger file.

defaultParams :: CInt -> CInt -> EncodingParams Source

Use default parameters for a video of the given width and height. The output format is determined by the output file name.

imageWriter :: forall p. JuicyPixelFormat p => EncodingParams -> FilePath -> IO (Maybe (Image p) -> IO ()) Source

Open a target file for writing a video stream. When the returned function is applied to Nothing, the output stream is closed. Note that Nothing must be provided when finishing in order to properly terminate video encoding.

Support for source images that are of a different size to the output resolution is limited to non-palettized destination formats (i.e. those that are handled by libswscaler). Practically, this means that animated gif output is only supported if the source images are of the target resolution.

Types and Enums