class FormatParser::DPXParser
include FormatParser::IOUtils
FILE_INFO = [
# :x4, # magic bytes SDPX, we read them anyway so not in the pattern
:x4, # u32 :image_offset, :desc => 'Offset to image data in bytes', :req => true
:x8, # char :version, 8, :desc => 'Version of header format', :req => true
:x4, # u32 :file_size, :desc => "Total image size in bytes", :req => true
:x4, # u32 :ditto_key, :desc => 'Whether the basic headers stay the same through the sequence (1 means they do)'
:x4, # u32 :generic_size, :desc => 'Generic header length'
:x4, # u32 :industry_size, :desc => 'Industry header length'
:x4, # u32 :user_size, :desc => 'User header length'
:x100, # char :filename, 100, :desc => 'Original filename'
:x24, # char :timestamp, 24, :desc => 'Creation timestamp'
:x100, # char :creator, 100, :desc => 'Creator application'
:x200, # char :project, 200, :desc => 'Project name'
:x200, # char :copyright, 200, :desc => 'Copyright'
:x4, # u32 :encrypt_key, :desc => 'Encryption key'
:x104, # blanking :reserve, 104
].join
FILM_INFO = [
:x2, # char :id, 2, :desc => 'Film mfg. ID code (2 digits from film edge code)'
:x2, # char :type, 2, :desc => 'Film type (2 digits from film edge code)'
:x2, # char :offset, 2, :desc => 'Offset in perfs (2 digits from film edge code)'
:x6, # char :prefix, 6, :desc => 'Prefix (6 digits from film edge code'
:x4, # char :count, 4, :desc => 'Count (4 digits from film edge code)'
:x32,# char :format, 32, :desc => 'Format (e.g. Academy)'
:x4, # u32 :frame_position, :desc => 'Frame position in sequence'
:x4, # u32 :sequence_extent, :desc => 'Sequence length'
:x4, # u32 :held_count, :desc => 'For how many frames the frame is held'
:x4, # r32 :frame_rate, :desc => 'Frame rate'
:x4, # r32 :shutter_angle, :desc => 'Shutter angle'
:x4, # char :frame_id, 32, :desc => 'Frame identification (keyframe)'
:x4, # char :slate, 100, :desc => 'Slate information'
:x4, # blanking :reserve, 56
].join
IMAGE_ELEMENT = [
:x4, # u32 :data_sign, :desc => 'Data sign (0=unsigned, 1=signed). Core is unsigned', :req => true
#
:x4, # u32 :low_data, :desc => 'Reference low data code value'
:x4, # r32 :low_quantity, :desc => 'Reference low quantity represented'
:x4, # u32 :high_data, :desc => 'Reference high data code value (1023 for 10bit per channel)'
:x4, # r32 :high_quantity, :desc => 'Reference high quantity represented'
#
:x1, # u8 :descriptor, :desc => 'Descriptor for this image element (ie Video or Film), by enum', :req => true
# TODO - colirimetry information might be handy to recover,
# as well as "bit size per element" (how many bits _per component_ we have) -
# this will be different for, say, 8-bit DPX files versus 10-bit etc.
:x1, # u8 :transfer, :desc => 'Transfer function (ie Linear), by enum', :req => true
:x1, # u8 :colorimetric, :desc => 'Colorimetric (ie YcbCr), by enum', :req => true
:x1, # u8 :bit_size, :desc => 'Bit size for element (ie 10)', :req => true
#
:x2, # u16 :packing, :desc => 'Packing (0=Packed into 32-bit words, 1=Filled to 32-bit words))', :req => true
:x2, # u16 :encoding, :desc => "Encoding (0=None, 1=RLE)", :req => true
:x4, # u32 :data_offset, :desc => 'Offset to data for this image element', :req => true
:x4, # u32 :end_of_line_padding, :desc => "End-of-line padding for this image element"
:x4, # u32 :end_of_image_padding, :desc => "End-of-line padding for this image element"
:x32,# char :description, 32
].join
IMAGE_INFO = [
:x2, # u16 :orientation, OrientationInfo, :desc => 'Orientation descriptor', :req => true
:n1, # u16 :number_elements, :desc => 'How many elements to scan', :req => true
:N1, # u32 :pixels_per_line, :desc => 'Pixels per horizontal line', :req => true
:N1, # u32 :lines_per_element, :desc => 'Line count', :req => true
IMAGE_ELEMENT * 8, # 8 IMAGE_ELEMENT structures
:x52, # blanking :reserve, 52
].join
ORIENTATION_INFO = [
:x4, # u32 :x_offset
:x4, # u32 :y_offset
#
:x4, # r32 :x_center
:x4, # r32 :y_center
#
:x4, # u32 :x_size, :desc => 'Original X size'
:x4, # u32 :y_size, :desc => 'Original Y size'
#
:x100, # char :filename, 100, :desc => "Source image filename"
:x24, # char :timestamp, 24, :desc => "Source image/tape timestamp"
:x32, # char :device, 32, :desc => "Input device or tape"
:x32, # char :serial, 32, :desc => "Input device serial number"
#
:x4, # array :border, :u16, 4, :desc => 'Border validity: XL, XR, YT, YB'
:x4,
:x4,
:x4,
# TODO - the aspect ratio might be handy to recover since it
# will be used in DPX files in, say, anamorphic (non-square pixels)
:x4, # array :aspect_ratio , :u32, 2, :desc => "Aspect (H:V)"
:x4,
#
:x28, # blanking :reserve, 28
].join
DPX_INFO = [
FILE_INFO,
IMAGE_INFO,
ORIENTATION_INFO,
].join
DPX_INFO_LE = DPX_INFO.tr("n", "v").tr("N", "V")
SIZEOF = ->(pattern) {
bytes_per_element = {
"v" => 2, # 16bit uints
"n" => 2,
"V" => 4, # 32bit uints
"N" => 4,
"C" => 1,
"x" => 1,
}
pattern.scan(/[^\d]\d+/).map do |pattern|
unpack_code = pattern[0]
num_repetitions = pattern[1..-1].to_i
bytes_per_element.fetch(unpack_code) * num_repetitions
end.inject(&:+)
}
BE_MAGIC = 'SDPX'
LE_MAGIC = BE_MAGIC.reverse
HEADER_SIZE = SIZEOF[DPX_INFO] # Does not include the initial 4 bytes
def information_from_io(io)
io = FormatParser::IOConstraint.new(io)
magic = io.read(4)
return nil unless [BE_MAGIC, LE_MAGIC].include?(magic)
unpack_pattern = DPX_INFO
unpack_pattern = DPX_INFO_LE if magic == LE_MAGIC
num_elements, pixels_per_line, num_lines, *_ = safe_read(io, HEADER_SIZE).unpack(unpack_pattern)
FormatParser::FileInformation.image(
file_type: :dpx,
width_px: pixels_per_line,
height_px: num_lines,
)
end
FormatParser.register_parser_constructor self
end