Package limn.video

package limn.video

Backend-neutral video: a pooled VideoFrame of planar YCbCr samples described by a PixelFormat layout and a VideoColor interpretation, produced by a VideoStreamSource that a VideoDecoder opened through the Videos facade, timed by VideoClock and shown by uploading it to a VideoSurface that the VideoSurfaces facade created, or, where no device conversion exists, turned into RGBA by YuvConverter.

Mirrors the audio package: the toolkit stays free of any media library and holds only the layout, the colour arithmetic and the timing policy; a backend supplies the decoders. Frames are borrowed and returned rather than allocated, because a picture is millions of bytes arriving tens of times a second.

Related Packages

Package	Description
limn.video.decode	Decoders, and the pooling every decoder needs.
limn.video.ffmpeg	H.264 and AAC out of MP4, through a trimmed FFmpeg behind a hand-written JNI shim.

Class	Description
AudioMasterClock	Reads a sounding audio playback's position as a VideoClock.MasterClock, so pictures are timed by the device that is actually making noise rather than by the wall clock.
MediaPlayer	Plays a video stream: a decode thread ahead of a small ring of pictures, a VideoClock timing them, and an optional audio track that becomes the clock's master.
MediaPlayer.State	Where a player is in its life.
MediaPlayer.Step	What one pass of the decode loop did: what a host driving it needs to know to pace itself.
PixelFormat	The memory layout of a decoded VideoFrame: how many planes it has, what each one holds, and how each plane's sample grid is derived from the frame size.
VideoClock	Decides, one candidate picture at a time, whether to show it, keep the current one, or throw it away: a player's whole timing policy, as arithmetic.
VideoClock.Decision	What the caller must do with the picture it just asked about.
VideoClock.MasterClock	A media position source on the same timeline as the pictures' presentation times.
VideoColor	How the samples of a VideoFrame are to be turned into colour: which luma/chroma matrix was used to encode them, whether the codes cover the full range or the studio range, and what transfer function the encoded values carry.
VideoColor.Matrix	The luma/chroma matrix a stream was encoded with.
VideoColor.Range	Which codes a stream's samples occupy.
VideoColor.Transfer	What the decoded values are, once the matrix has been undone: numbers a display can show, or a curve that has to be inverted before they mean light.
VideoDecoder	Opens a video input for incremental decoding.
VideoFrame	One decoded picture, borrowed from the producer that published it.
VideoFrame.Downloader	How a producer reads one of its own device pictures back into memory a consumer can address, when VideoFrame.toPlanar() asks it to.
VideoFrame.Kind	Which of the two shapes a picture has: samples in memory, or a handle to a device allocation.
VideoFrame.Recycler	How a producer gets a released frame's memory back.
VideoFrame.Writer	A producer's handle on one pooled frame: the only thing that can point a frame at memory or publish it.
Videos	Video facade, over the installed VideoDecoders.
VideoStreamSource	A pull source of decoded pictures: the video counterpart of an incrementally decoded audio stream, obtained from a VideoDecoder and driven one picture at a time.
VideoStreamSource.Read	The outcome of a VideoStreamSource.readFrame() call.
VideoStreamSource.SeekMode	How close to the target a seek is asked to land.
VideoSurface	A device-side picture: the destination a VideoFrame's planar samples are uploaded to, converted to colour by the backend, and composited by Canvas.drawSurface(limn.graphics.GpuSurface, float, float, float, float) as one quad in the 2D paint order, so clipping, opacity, overlays and dialogs apply to a video exactly as they apply to a rectangle.
VideoSurfaces	Video-surface facade + install-at-startup SPI (the same inversion as the image, audio and 3D facades): a neutral entry point here, the device implementation installed by the backend.
VideoSurfaces.Provider	Backend-supplied factory, installed at startup.
YuvConverter	Converts a decoded picture to 8-bit RGBA on the CPU: the reference implementation of the colour arithmetic, and the path used where no device conversion is available.