IVF is a simple container format for raw VP8 data, which is an open and royalty-free video compression format, currently developed by Google.
Test .ivf files are available at https://chromium.googlesource.com/webm/vp8-test-vectors
This page hosts a formal specification of VP8 raw file using Kaitai Struct. This specification can be automatically translated into a variety of programming languages to get a parsing library.
-- This is a generated file! Please edit source .ksy file and use kaitai-struct-compiler to rebuild
--
-- This file is compatible with Lua 5.3
local class = require("class")
require("kaitaistruct")
--
-- IVF is a simple container format for raw VP8 data, which is an open and
-- royalty-free video compression format, currently developed by Google.
--
-- Test .ivf files are available at
-- <https://chromium.googlesource.com/webm/vp8-test-vectors>
-- See also: Source (https://wiki.multimedia.cx/index.php/IVF)
Vp8Ivf = class.class(KaitaiStruct)
function Vp8Ivf:_init(io, parent, root)
KaitaiStruct._init(self, io)
self._parent = parent
self._root = root or self
self:_read()
end
function Vp8Ivf:_read()
self.magic1 = self._io:read_bytes(4)
if not(self.magic1 == "\068\075\073\070") then
error("not equal, expected " .. "\068\075\073\070" .. ", but got " .. self.magic1)
end
self.version = self._io:read_u2le()
self.len_header = self._io:read_u2le()
self.codec = self._io:read_bytes(4)
if not(self.codec == "\086\080\056\048") then
error("not equal, expected " .. "\086\080\056\048" .. ", but got " .. self.codec)
end
self.width = self._io:read_u2le()
self.height = self._io:read_u2le()
self.framerate = self._io:read_u4le()
self.timescale = self._io:read_u4le()
self.num_frames = self._io:read_u4le()
self.unused = self._io:read_u4le()
self.image_data = {}
for i = 0, self.num_frames - 1 do
self.image_data[i + 1] = Vp8Ivf.Blocks(self._io, self, self._root)
end
end
--
-- Magic Number of IVF Files.
--
-- This should be 0.
--
-- Normally the header length is 32 byte.
--
-- Name of the codec e.g. 'VP80' for VP8.
--
-- The (initial) width of the video, every keyframe may change the resolution.
--
-- The (initial) height of the video, every keyframe may change the resolution.
--
-- the (framerate * timescale) e.g. for 30 fps -> 30000.
--
-- the timescale is a divider of the seconds (VPX is integer math only) mostly 1000.
--
-- the number of frames (if not a camera stream).
Vp8Ivf.Blocks = class.class(KaitaiStruct)
function Vp8Ivf.Blocks:_init(io, parent, root)
KaitaiStruct._init(self, io)
self._parent = parent
self._root = root or self
self:_read()
end
function Vp8Ivf.Blocks:_read()
self.entries = Vp8Ivf.Block(self._io, self, self._root)
end
Vp8Ivf.Block = class.class(KaitaiStruct)
function Vp8Ivf.Block:_init(io, parent, root)
KaitaiStruct._init(self, io)
self._parent = parent
self._root = root or self
self:_read()
end
function Vp8Ivf.Block:_read()
self.len_frame = self._io:read_u4le()
self.timestamp = self._io:read_u8le()
self.framedata = self._io:read_bytes(self.len_frame)
end
--
-- size of the frame data.