mirror of
https://github.com/wader/fq.git
synced 2024-12-02 04:05:35 +03:00
96 lines
2.2 KiB
Go
96 lines
2.2 KiB
Go
package av1
|
|
|
|
import (
|
|
"github.com/wader/fq/format"
|
|
"github.com/wader/fq/format/registry"
|
|
"github.com/wader/fq/pkg/decode"
|
|
)
|
|
|
|
func init() {
|
|
registry.MustRegister(&decode.Format{
|
|
Name: format.AV1_OBU,
|
|
Description: "AV1 Open Bitstream Unit",
|
|
DecodeFn: obuDecode,
|
|
})
|
|
}
|
|
|
|
//nolint:revive
|
|
const (
|
|
OBU_SEQUENCE_HEADER = 1
|
|
OBU_TEMPORAL_DELIMITER = 2
|
|
OBU_FRAME_HEADER = 3
|
|
OBU_TILE_GROUP = 4
|
|
OBU_METADATA = 5
|
|
OBU_FRAME = 6
|
|
OBU_REDUNDANT_FRAME_HEADER = 7
|
|
OBU_TILE_LIST = 8
|
|
OBU_PADDING = 15
|
|
)
|
|
|
|
var obuTypeNames = map[uint64]string{
|
|
OBU_SEQUENCE_HEADER: "OBU_SEQUENCE_HEADER",
|
|
OBU_TEMPORAL_DELIMITER: "OBU_TEMPORAL_DELIMITER",
|
|
OBU_FRAME_HEADER: "OBU_FRAME_HEADER",
|
|
OBU_TILE_GROUP: "OBU_TILE_GROUP",
|
|
OBU_METADATA: "OBU_METADATA",
|
|
OBU_FRAME: "OBU_FRAME",
|
|
OBU_REDUNDANT_FRAME_HEADER: "OBU_REDUNDANT_FRAME_HEADER",
|
|
OBU_TILE_LIST: "OBU_TILE_LIST",
|
|
OBU_PADDING: "OBU_PADDING",
|
|
}
|
|
|
|
func leb128(d *decode.D) uint64 {
|
|
var v uint64
|
|
for i := 0; i < 8; i++ {
|
|
b := d.U8()
|
|
v = v | (b&0x7f)<<(i*7)
|
|
if b&0x80 == 0 {
|
|
break
|
|
}
|
|
}
|
|
return v
|
|
}
|
|
|
|
func fieldLeb128(d *decode.D, name string) uint64 {
|
|
return d.FieldUFn(name, func() (uint64, decode.DisplayFormat, string) {
|
|
return leb128(d), decode.NumberDecimal, ""
|
|
})
|
|
}
|
|
|
|
func obuDecode(d *decode.D, in interface{}) interface{} {
|
|
var obuType uint64
|
|
var obuSize int64
|
|
hasExtension := false
|
|
hasSizeField := false
|
|
|
|
d.FieldStructFn("header", func(d *decode.D) {
|
|
d.FieldU1("forbidden_bit")
|
|
obuType, _ = d.FieldStringMapFn("type", obuTypeNames, "Reserved", d.U4, decode.NumberDecimal)
|
|
hasExtension = d.FieldBool("extension_flag")
|
|
hasSizeField = d.FieldBool("has_size_field")
|
|
d.FieldU1("reserved_1bit")
|
|
if hasExtension {
|
|
d.FieldU3("temporal_id")
|
|
d.FieldU2("spatial_id")
|
|
d.FieldU3("extension_header_reserved_3bits")
|
|
}
|
|
})
|
|
|
|
if hasSizeField {
|
|
obuSize = int64(fieldLeb128(d, "size"))
|
|
} else {
|
|
obuSize = d.BitsLeft() / 8
|
|
if hasExtension {
|
|
obuSize--
|
|
}
|
|
}
|
|
|
|
_ = obuType
|
|
|
|
if d.BitsLeft() > 0 {
|
|
d.FieldBitBufLen("data", obuSize*8)
|
|
}
|
|
|
|
return nil
|
|
}
|