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mirror of https://github.com/wader/fq.git synced 2024-11-28 11:42:50 +03:00
fq/format/mpeg/aac_frame.go
Mattias Wadman f4480c6fe5 decode,interp: Support for format specific options
interp: Refactor format help and also include options
interp: Add -o name=@path to load file content as value (not documented yet, might change)
interp,decode: Expose decode out value as _out (might change)
interp: Refactor foramts.jq into format_{decode,func,include}.jq
interp: Refactor torepr into _format_func for generic format function overloading
interp: Refactor -o options parsing to be more generic and collect unknowns options to be used as format options
decode of decode alises
func for format overloaded functions
include for format specific jq functions (also _help, torepr etc)
flac_frame: Add bits_per_sample option
mp3: Add max_unique_header_config and max_sync_seek options
mp4: Add decode_samples and allow_truncate options
avc_au: Has length_size option
hevc_au: Has length_size option
aac_frame: Has object_typee option
doc: Rewrite format doc generation, less hack more jq
2022-05-01 17:08:30 +02:00

329 lines
8.2 KiB
Go

package mpeg
// one AAC frame or "raw data block"
// ISO/IEC 13818-7 Part 7: Advanced Audio Coding (AAC)
// ISO/IEC 14496-3
// TODO: currently only does very basic main, lc, ssr and ltp
import (
"github.com/wader/fq/format"
"github.com/wader/fq/format/registry"
"github.com/wader/fq/pkg/decode"
"github.com/wader/fq/pkg/scalar"
)
func init() {
registry.MustRegister(decode.Format{
Name: format.AAC_FRAME,
Description: "Advanced Audio Coding frame",
DecodeFn: aacDecode,
DecodeInArg: format.AACFrameIn{
ObjectType: format.MPEGAudioObjectTypeMain,
},
RootArray: true,
RootName: "elements",
})
}
const (
SCE = 0b000
CPE = 0b001
CCE = 0b010
LFE = 0b011
DSE = 0b100
PCE = 0b101
FIL = 0b110
TERM = 0b111
)
var syntaxElementNames = scalar.UToSymStr{
SCE: "SCE",
CPE: "CPE",
CCE: "CCE",
LFE: "LFE",
DSE: "DSE",
PCE: "PCE",
FIL: "FIL",
TERM: "TERM",
}
//nolint:revive
const (
EXT_FILL = 0x0
EXT_FILL_DATA = 0x1
EXT_DATA_ELEMENT = 0x2
EXT_DYNAMIC_RANGE = 0xb
EXT_SBR_DATA = 0xd
EXT_SBR_DATA_CRC = 0xe
)
var extensionPayloadIDNames = scalar.UToSymStr{
EXT_FILL: "EXT_FILL",
EXT_FILL_DATA: "EXT_FILL_DATA",
EXT_DATA_ELEMENT: "EXT_DATA_ELEMENT",
EXT_DYNAMIC_RANGE: "EXT_DYNAMIC_RANGE",
EXT_SBR_DATA: "EXT_SBR_DATA",
EXT_SBR_DATA_CRC: "EXT_SBR_DATA_CRC",
}
//nolint:revive
const (
ONLY_LONG_SEQUENCE = 0x0
LONG_START_SEQUENCE = 0x1
EIGHT_SHORT_SEQUENCE = 0x2
LONG_STOP_SEQUENCE = 0x3
)
var windowSequenceNames = scalar.UToSymStr{
ONLY_LONG_SEQUENCE: "ONLY_LONG_SEQUENCE",
LONG_START_SEQUENCE: "LONG_START_SEQUENCE",
EIGHT_SHORT_SEQUENCE: "EIGHT_SHORT_SEQUENCE",
LONG_STOP_SEQUENCE: "LONG_STOP_SEQUENCE",
}
var windowSequenceNumWindows = map[int]int{
ONLY_LONG_SEQUENCE: 1,
LONG_START_SEQUENCE: 1,
EIGHT_SHORT_SEQUENCE: 8,
LONG_STOP_SEQUENCE: 1,
}
func aacLTPData(d *decode.D, objectType int, windowSequence int) {
switch objectType {
case format.MPEGAudioObjectTypeER_AAC_LD:
// TODO:
default:
d.FieldU11("ltp_lag")
d.FieldU3("ltp_coef")
_ = windowSequenceNumWindows[windowSequence]
}
}
func aacICSInfo(d *decode.D, objectType int) {
d.FieldU1("ics_reserved_bit")
windowSequence := d.FieldU2("window_sequence", windowSequenceNames)
d.FieldU1("window_shape")
switch windowSequence {
case EIGHT_SHORT_SEQUENCE:
d.FieldU4("max_sfb")
d.FieldU7("scale_factor_grouping")
default:
maxSFB := d.FieldU6("max_sfb")
predictorDataPresent := d.FieldBool("predictor_data_present")
if predictorDataPresent {
switch objectType {
case format.MPEGAudioObjectTypeMain: // 1
predictorReset := d.FieldBool("predictor_reset")
if predictorReset {
d.FieldU5("predictor_reset_group_number")
}
d.FieldU5("predictor_reset_group_number")
// TODO: min(max_sfb, PRED_SFB_MAX)
// TODO: array?
d.FieldRawLen("prediction_used", int64(maxSFB))
default:
ltpDataPresent := d.FieldBool("ltp_data_present")
if ltpDataPresent {
aacLTPData(d, objectType, int(windowSequence))
}
}
}
}
// ;
// if (window_sequence == EIGHT_SHORT_SEQUENCE) {
// max_sfb; scale_factor_grouping;
// } }
// else {
// ltp_data_present;
// if (ltp_data_present) {
// ltp_data(); }
// if (common_window) {
// ltp_data_present;
// LICENSED TO MECON Limited. - RANCHI/BANGALORE,
// FOR INTERNAL USE AT THIS LOCATION ONLY, SUPPLIED BY BOOK SUPPLY BUREAU.
// if (ltp_data_present) {
// ltp_data(); }
// } }
// } }
// }
}
func aacIndividualChannelStream(d *decode.D, objectType int, commonWindow bool, scaleFlag bool) {
d.FieldU8("global_gain")
if !commonWindow && !scaleFlag {
d.FieldStruct("ics_info", func(d *decode.D) {
aacICSInfo(d, objectType)
})
}
}
func aacSingleChannelElement(d *decode.D, objectType int) {
d.FieldU4("element_instance_tag")
aacIndividualChannelStream(d, objectType, false, false)
}
func aacProgramConfigElement(d *decode.D, ascStartPos int64) {
d.FieldU4("element_instance_tag")
d.FieldU2("object_type")
d.FieldU4("sampling_frequency_index")
numFrontChannelElements := d.FieldU4("num_front_channel_elements")
numSideChannelElements := d.FieldU4("num_side_channel_elements")
numBackChannelElements := d.FieldU4("num_back_channel_elements")
numLfeChannelElements := d.FieldU2("num_lfe_channel_elements")
numAssocDataElements := d.FieldU3("num_assoc_data_elements")
numValidCcElements := d.FieldU4("num_valid_cc_elements")
monoMixdownPresent := d.FieldBool("mono_mixdown_present")
if monoMixdownPresent {
d.FieldU4("mono_mixdown_element_number")
}
stereoMixdownPresent := d.FieldBool("stereo_mixdown_present")
if stereoMixdownPresent {
d.FieldU4("stereo_mixdown_element_number")
}
matrixMixdownIdxPresent := d.FieldBool("matrix_mixdown_idx_present")
if matrixMixdownIdxPresent {
d.FieldU2("matrix_mixdown_idx")
d.FieldBool("pseudo_surround_enable")
}
d.FieldArray("front_channel_elements", func(d *decode.D) {
for i := uint64(0); i < numFrontChannelElements; i++ {
d.FieldStruct("front_channel_element", func(d *decode.D) {
d.FieldBool("is_cpe")
d.FieldU4("tag_select")
})
}
})
d.FieldArray("side_channel_elements", func(d *decode.D) {
for i := uint64(0); i < numSideChannelElements; i++ {
d.FieldStruct("side_channel_element", func(d *decode.D) {
d.FieldBool("is_cpe")
d.FieldU4("tag_select")
})
}
})
d.FieldArray("back_channel_elements", func(d *decode.D) {
for i := uint64(0); i < numBackChannelElements; i++ {
d.FieldStruct("back_channel_element", func(d *decode.D) {
d.FieldBool("is_cpe")
d.FieldU4("tag_select")
})
}
})
d.FieldArray("lfe_channel_elements", func(d *decode.D) {
for i := uint64(0); i < numLfeChannelElements; i++ {
d.FieldStruct("lfe_channel_element", func(d *decode.D) {
d.FieldU4("tag_select")
})
}
})
d.FieldArray("assoc_data_elements", func(d *decode.D) {
for i := uint64(0); i < numAssocDataElements; i++ {
d.FieldStruct("assoc_data_element", func(d *decode.D) {
d.FieldU4("tag_select")
})
}
})
d.FieldArray("valid_cc_elements", func(d *decode.D) {
for i := uint64(0); i < numValidCcElements; i++ {
d.FieldStruct("valid_cc_element", func(d *decode.D) {
d.FieldU1("cc_element_is_ind_sw")
d.FieldU4("valid_cc_element_tag_select")
})
}
})
byteAlignBits := (8 - ((d.Pos() + ascStartPos) & 0x7)) & 0x7
d.FieldRawLen("byte_alignment", byteAlignBits)
commentFieldBytes := d.FieldU8("comment_field_bytes")
d.FieldUTF8("comment_field", int(commentFieldBytes))
}
func aacFillElement(d *decode.D) {
var cnt uint64
d.FieldStruct("cnt", func(d *decode.D) {
count := d.FieldU4("count")
cnt = count
if cnt == 15 {
escCount := d.FieldU8("esc_count")
cnt += escCount - 1
}
})
d.FieldValueU("payload_length", cnt)
d.FieldStruct("extension_payload", func(d *decode.D) {
d.FramedFn(int64(cnt)*8, func(d *decode.D) {
extensionType := d.FieldU4("extension_type", extensionPayloadIDNames)
// d.FieldU("align4", 2)
switch extensionType {
case EXT_FILL:
d.FieldU4("fill_nibble")
d.FieldRawLen("fill_byte", 8*(int64(cnt)-1))
}
})
})
}
func aacDecode(d *decode.D, in interface{}) interface{} {
var objectType int
if afi, ok := in.(format.AACFrameIn); ok {
objectType = afi.ObjectType
}
// TODO: seems tricky to know length of blocks
// TODO: currently break when length is unknown
switch objectType {
case format.MPEGAudioObjectTypeMain,
format.MPEGAudioObjectTypeLC,
format.MPEGAudioObjectTypeSSR,
format.MPEGAudioObjectTypeLTP,
format.MPEGAudioObjectTypeSBR,
format.MPEGAudioObjectTypeER_AAC_LD,
format.MPEGAudioObjectTypePS:
seenTerm := false
for !seenTerm {
d.FieldStruct("element", func(d *decode.D) {
se := d.FieldU3("syntax_element", syntaxElementNames)
switch se {
case FIL:
aacFillElement(d)
case SCE:
aacSingleChannelElement(d, objectType)
seenTerm = true
case PCE:
aacProgramConfigElement(d, 0)
seenTerm = true
default:
fallthrough
case TERM:
seenTerm = true
}
})
}
if d.ByteAlignBits() > 0 {
d.FieldRawLen("byte_align", int64(d.ByteAlignBits()))
}
d.FieldRawLen("data", d.BitsLeft())
default:
// not supported
d.FieldRawLen("data", d.BitsLeft())
}
return nil
}