av/container/mts/encoder_test.go

253 lines
6.8 KiB
Go

/*
NAME
encoder_test.go
AUTHOR
Trek Hopton <trek@ausocean.org>
Saxon A. Nelson-Milton <saxon@ausocean.org>
LICENSE
encoder_test.go is Copyright (C) 2017-2019 the Australian Ocean Lab (AusOcean)
It is free software: you can redistribute it and/or modify them
under the terms of the GNU General Public License as published by the
Free Software Foundation, either version 3 of the License, or (at your
option) any later version.
It is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
You should have received a copy of the GNU General Public License in gpl.txt.
If not, see http://www.gnu.org/licenses.
*/
package mts
import (
"bytes"
"io"
"io/ioutil"
"testing"
"github.com/Comcast/gots/packet"
"github.com/Comcast/gots/pes"
"bitbucket.org/ausocean/av/container/mts/meta"
)
type nopCloser struct{ io.Writer }
func (nopCloser) Close() error { return nil }
type destination struct {
packets [][]byte
}
func (d *destination) Write(p []byte) (int, error) {
tmp := make([]byte, PacketSize)
copy(tmp, p)
d.packets = append(d.packets, tmp)
return len(p), nil
}
// TestEncodeVideo checks that we can correctly encode some dummy data into a
// valid MPEG-TS stream. This checks for correct MPEG-TS headers and also that the
// original data is stored correctly and is retreivable.
func TestEncodeVideo(t *testing.T) {
Meta = meta.New()
const dataLength = 440
const numOfPackets = 3
const stuffingLen = 100
// Generate test data.
data := make([]byte, 0, dataLength)
for i := 0; i < dataLength; i++ {
data = append(data, byte(i))
}
// Expect headers for PID 256 (video)
// NB: timing fields like PCR are neglected.
expectedHeaders := [][]byte{
{
0x47, // Sync byte.
0x41, // TEI=0, PUSI=1, TP=0, PID=00001 (256).
0x00, // PID(Cont)=00000000.
0x30, // TSC=00, AFC=11(adaptation followed by payload), CC=0000(0).
0x07, // AFL= 7.
0x50, // DI=0,RAI=1,ESPI=0,PCRF=1,OPCRF=0,SPF=0,TPDF=0, AFEF=0.
},
{
0x47, // Sync byte.
0x01, // TEI=0, PUSI=0, TP=0, PID=00001 (256).
0x00, // PID(Cont)=00000000.
0x31, // TSC=00, AFC=11(adaptation followed by payload), CC=0001(1).
0x01, // AFL= 1.
0x00, // DI=0,RAI=0,ESPI=0,PCRF=0,OPCRF=0,SPF=0,TPDF=0, AFEF=0.
},
{
0x47, // Sync byte.
0x01, // TEI=0, PUSI=0, TP=0, PID=00001 (256).
0x00, // PID(Cont)=00000000.
0x32, // TSC=00, AFC=11(adaptation followed by payload), CC=0010(2).
0x57, // AFL= 1+stuffingLen.
0x00, // DI=0,RAI=0,ESPI=0,PCRF=1,OPCRF=0,SPF=0,TPDF=0, AFEF=0.
},
}
// Create the dst and write the test data to encoder.
dst := &destination{}
_, err := NewEncoder(nopCloser{dst}, 25, EncodeH264).Write(data)
if err != nil {
t.Fatalf("could not write data to encoder, failed with err: %v\n", err)
}
// Check headers.
var expectedIdx int
for _, p := range dst.packets {
// Get PID.
var _p packet.Packet
copy(_p[:], p)
pid := packet.Pid(&_p)
if pid == VideoPid {
// Get mts header, excluding PCR.
gotHeader := p[0:6]
wantHeader := expectedHeaders[expectedIdx]
if !bytes.Equal(gotHeader, wantHeader) {
t.Errorf("did not get expected header for idx: %v.\n Got: %v\n Want: %v\n", expectedIdx, gotHeader, wantHeader)
}
expectedIdx++
}
}
// Gather payload data from packets to form the total PES packet.
var pesData []byte
for _, p := range dst.packets {
var _p packet.Packet
copy(_p[:], p)
pid := packet.Pid(&_p)
if pid == VideoPid {
payload, err := packet.Payload(&_p)
if err != nil {
t.Fatalf("could not get payload from mts packet, failed with err: %v\n", err)
}
pesData = append(pesData, payload...)
}
}
// Get data from the PES packet and compare with the original data.
pes, err := pes.NewPESHeader(pesData)
if err != nil {
t.Fatalf("got error from pes creation: %v\n", err)
}
_data := pes.Data()
if !bytes.Equal(data, _data) {
t.Errorf("did not get expected result.\n Got: %v\n Want: %v\n", data, _data)
}
}
// TestEncodePcm tests the MPEG-TS encoder's ability to encode pcm audio data.
// It reads and encodes input pcm data into MPEG-TS, then decodes the MPEG-TS and compares the result to the input pcm.
func TestEncodePcm(t *testing.T) {
Meta = meta.New()
var buf bytes.Buffer
sampleRate := 48000
sampleSize := 2
blockSize := 16000
writeFreq := float64(sampleRate*sampleSize) / float64(blockSize)
e := NewEncoder(nopCloser{&buf}, writeFreq, EncodeAudio)
inPath := "../../../test/test-data/av/input/sweep_400Hz_20000Hz_-3dBFS_5s_48khz.pcm"
inPcm, err := ioutil.ReadFile(inPath)
if err != nil {
t.Errorf("unable to read file: %v", err)
}
// Break pcm into blocks and encode to mts and get the resulting bytes.
for i := 0; i < len(inPcm); i += blockSize {
if len(inPcm)-i < blockSize {
block := inPcm[i:]
_, err = e.Write(block)
if err != nil {
t.Errorf("unable to write block: %v", err)
}
} else {
block := inPcm[i : i+blockSize]
_, err = e.Write(block)
if err != nil {
t.Errorf("unable to write block: %v", err)
}
}
}
clip := buf.Bytes()
// Get the first MTS packet to check
var pkt packet.Packet
pesPacket := make([]byte, 0, blockSize)
got := make([]byte, 0, len(inPcm))
i := 0
if i+PacketSize <= len(clip) {
copy(pkt[:], clip[i:i+PacketSize])
}
// Loop through MTS packets until all the audio data from PES packets has been retrieved
for i+PacketSize <= len(clip) {
// Check MTS packet
if !(pkt.PID() == audioPid) {
i += PacketSize
if i+PacketSize <= len(clip) {
copy(pkt[:], clip[i:i+PacketSize])
}
continue
}
if !pkt.PayloadUnitStartIndicator() {
i += PacketSize
if i+PacketSize <= len(clip) {
copy(pkt[:], clip[i:i+PacketSize])
}
} else {
// Copy the first MTS payload
payload, err := pkt.Payload()
if err != nil {
t.Errorf("unable to get MTS payload: %v", err)
}
pesPacket = append(pesPacket, payload...)
i += PacketSize
if i+PacketSize <= len(clip) {
copy(pkt[:], clip[i:i+PacketSize])
}
// Copy the rest of the MTS payloads that are part of the same PES packet
for (!pkt.PayloadUnitStartIndicator()) && i+PacketSize <= len(clip) {
payload, err = pkt.Payload()
if err != nil {
t.Errorf("unable to get MTS payload: %v", err)
}
pesPacket = append(pesPacket, payload...)
i += PacketSize
if i+PacketSize <= len(clip) {
copy(pkt[:], clip[i:i+PacketSize])
}
}
}
// Get the audio data from the current PES packet
pesHeader, err := pes.NewPESHeader(pesPacket)
if err != nil {
t.Errorf("unable to read PES packet: %v", err)
}
got = append(got, pesHeader.Data()...)
pesPacket = pesPacket[:0]
}
// Compare data from MTS with original data.
if !bytes.Equal(got, inPcm) {
t.Error("data decoded from mts did not match input data")
}
}