# node-fdkaac node-fdkaac logo Fraunhofer FDK AAC is a high-quality open-source AAC encoder. For all AAC and M4A encoding needs, a Node.js wrapper of the full [fdkaac](https://github.com/nu774/fdkaac) command line frontend (by [nu774](https://github.com/nu774)) based on [libfdk-aac](https://github.com/mstorsjo/fdk-aac) encoder. The encoder reads linear PCM audio in either WAV, raw PCM or CAF format and encodes it into an M4A or an AAC file. ## Requirements - Linux or MacOS (Windows is NOT support by this package) - libfdk-aac, fdkaac and ffmpeg installed (instructions see below) - node 18.20.\* or newer ## Installation You can install it with `npm`: ```bash $ npm install --save node-fdkaac ``` If you have not installed [libfdk-aac](https://github.com/mstorsjo/fdk-aac), [fdkaac](https://github.com/nu774/fdkaac) and [ffmpeg](https://www.ffmpeg.org/) yet, you find a bash script to compile the source code as `install.sh` in this package. _install.sh requirements:_ - automake - libtool - git ### Run on Debian ```bash $ sudo apt-get install automake libtool git ffmpeg $ chmod +x install.sh $ sudo ./install.sh ``` ### Run on MacOS with brew ```bash $ brew install automake libtool git ffmpeg $ chmod +x install.sh $ sudo ./install.sh ``` ## Example ### Encode from file to file ```node const Fdkaac = require("node-fdkaac").Fdkaac; const encoder = new Fdkaac({ output: "./audio-files/demo.m4a", bitrate: 192, }).setFile("./audio-files/demo.wav"); encoder .encode() .then(() => { // Encoding finished }) .catch((error) => { // Something went wrong }); ``` ### Encode from file to buffer ```node const Fdkaac = require("node-fdkaac").Fdkaac; const encoder = new Fdkaac({ output: "buffer", bitrate: 192, }).setFile("./audio-files/demo.wav"); encoder .encode() .then(() => { // Encoding finished const buffer = encoder.getBuffer(); }) .catch((error) => { // Something went wrong }); ``` ### Encode from buffer to file ```node [...] const Fdkaac = require("node-fdkaac").Fdkaac; const encoder = new Fdkaac({ "output": "./audio-files/demo.m4a", "bitrate": 192 }).setBuffer(audioFileBuffer); encoder.encode() .then(() => { // Encoding finished }) .catch((error) => { // Something went wrong }); ``` ### Encode from buffer to buffer ```node [...] const Fdkaac = require("node-fdkaac").Fdkaac; const encoder = new Fdkaac({ "output": "buffer", "bitrate": 192 }).setBuffer(audioFileBuffer); encoder.encode() .then(() => { // Encoding finished const buffer = encoder.getBuffer(); }) .catch((error) => { // Something went wrong }); ``` ### Get status of encoder as object ```node const Fdkaac = require("node-fdkaac").Fdkaac; const encoder = new Fdkaac({ output: "buffer", bitrate: 192, }).setFile("./audio-files/demo.wav"); encoder .encode() .then(() => { // Encoding finished }) .catch((error) => { // Something went wrong }); const status = encoder.getStatus(); ``` ### Get status of encoder as EventEmitter ```node const Fdkaac = require("node-fdkaac").Fdkaac; const encoder = new Fdkaac({ output: "buffer", bitrate: 192, }).setFile("./audio-files/demo.wav"); const emitter = encoder.getEmitter(); emitter.on("progress", ([progress, eta]) => { // On progress of encoding; in percent and estimated time of arrival as 00:00 }); emitter.on("finish", () => { // On finish }); emitter.on("error", (error) => { // On error }); encoder .encode() .then(() => { // Encoding finished }) .catch((error) => { // Something went wrong }); ``` ### Decode from file to file ```node const Fdkaac = require("node-fdkaac").Fdkaac; const decoder = new Fdkaac({ output: "./audio-files/demo.wav", }).setFile("./audio-files/demo.m4a"); decoder .decode() .then(() => { // Decoding finished }) .catch((error) => { // Something went wrong }); ``` ### Decode from file to buffer ```node const Fdkaac = require("node-fdkaac").Fdkaac; const decoder = new Lame({ output: "buffer", }).setFile("./audio-files/demo.m4a"); decoder .decode() .then(() => { // Decoding finished const buffer = decoder.getBuffer(); }) .catch((error) => { // Something went wrong }); ``` ### Decode from buffer to file ```node [...] const Fdkaac = require("node-fdkaac").Fdkaac; const decoder = new Lame({ "output": "./audio-files/demo.wav" }).setBuffer(m4aInputBuffer); decoder.decode() .then(() => { // Decoding finished }) .catch((error) => { // Something went wrong }); ``` ### Decode from buffer to buffer ```node [...] const Fdkaac = require("node-fdkaac").Fdkaac; const decoder = new Lame({ "output": "buffer" }).setBuffer(mp4aInputBuffer); decoder.decode() .then(() => { // Decoding finished const buffer = decoder.getBuffer(); }) .catch((error) => { // Something went wrong }); ``` ## All options | Option | Description | Values | Default | | ----------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------- | ----------- | | output | Output filename | Path | | profile | Target profile (MPEG4 audio object type, AOT) | `2` (MPEG-4 AAC LC), `5` (MPEG-4 HE-AAC; SBR), `23` (MPEG-4 AAC LD), `29` (MPEG-4 HE-AAC v2; SBR+PS), `39` (MPEG-4 AAC ELD) | `2` | | bitrate | Target bitrate (for CBR) | Number | `undefined` | | bitrate-mode | Bitrate configuration mode. Available VBR quality value depends on other parameters such as profile, sample rate, or number of channels. | `0` (CBR), `1`-`5` (VBR; higher value => higher bitrate) | `0` | | bandwidth | Frequency bandwidth (lowpass cut-off frequency) in Hz. Available on AAC LC only. | Number | `undefined` | | afterburner | Configure afterburner mode. When enabled, quality is increased at the expense of additional computational workload. | `0` (Off), `1` (On) | `1` | | lowdelay-sbr | Configure SBR activity on AAC ELD. | `-1` (Use ELD SBR auto configuration, `0` (Disable SBR on ELD), `1` (Enable SBR on ELD) | `0` | | sbr-ratio | Controls activation of downsampled SBR. | `0` (Use lib default), `1` (Use downsampled SBR; default for ELD+SBR), `2` (Use dual-rate SBR; default for HE-AAC) | `0` | | transport-format | Transport format. Tagging and gapless playback is only available on M4A. | `0` (M4A), `1` (ADIF), `2` (ADTS), `6` (LATM MCP=1), `7` (LATM MCP=0), `10` (LOAS/LATM; LATM within LOAS) | `0` | | adts-crc-check | Add CRC protection on ADTS header. | Boolean | `false` | | header-period | StreamMuxConfig/PCE repetition period in the transport layer. | Number | `undefined` | | gapless-mode | Method to declare amount of encoder delay (and padding) in M4A container. These values are mandatory for proper gapless playback on player side. | `0` (iTunSMPB), `1` (ISO standard; edts and sgpd), `2` (Both) | `0` | | include-sbr-delay | When specified, count SBR decoder delay in encoder delay. | Boolean | `false` | | ignorelength | Ignore length field of data chunk in input WAV file. | Boolean | `false` | | moov-before-mdat | Place moov box before mdat box in M4A container. This option might be important for some hardware players, that are known to refuse moov box placed after mdat box. | Boolean | `false` | | raw | Regard input as raw PCM. | Boolean | `false` | | raw-channels | Specify number of channels of raw input | Number | `2` | | raw-rate | Specify sample rate of raw input. | Number | `44100` | | raw-format | Specify sample format of raw input (details see [nu774/fdkaac](https://github.com/nu774/fdkaac/blob/master/README)). | String | `S16L` | | meta | Meta data for M4A container. | Object | `undefined` | _Meta options_ | Option | Description | Values | Default | | ------------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------------ | ----------------- | ----------- | | title | Set title tag. | String | `undefined` | | artist | Set artist tag. | String | `undefined` | | album | Set album tag. | String | `undefined` | | genre | Set genre tag. | String | `undefined` | | date | Set date tag. | String | `undefined` | | composer | Set composer tag. | String | `undefined` | | grouping | Set grouping tag. | String | `undefined` | | comment | Set comment tag. | String | `undefined` | | album-artist | Set album artist tag. | String | `undefined` | | track | Set track tag, with or without number of total tracks. | Number[/Total] | `undefined` | | disk | Set disk tag, with or without number of total discs. | Number[/Total] | `undefined` | | tempo | Set tempo (BPM) tag. | Number | `undefined` | | tag | Set iTunes predefined tag with explicit fourcc key and value. See [iTunesMetadata](https://code.google.com/p/mp4v2/wiki/iTunesMetadata) for known predefined keys. | \:\ | `undefined` | | long-tag | Set arbitrary tag as iTunes custom metadata. Stored in com.apple.iTunes field. | \:\ | `undefined` | Option description text from [fdkaac](https://github.com/nu774/fdkaac) by [nu774](https://github.com/nu774). Based on fdkaac commit [4682fe4](https://github.com/nu774/fdkaac/tree/4682fe4961b92d3872e47d9fd4d9256151d292e7) from Jan 16, 2017.