strf

packages/media-parser/src/boxes/riff/parse-riff-box.ts

@@ -4,6 +4,7 @@ import {parseFmtBox} from './parse-fmt-box';
 import {parseListBox} from './parse-list-box';
 import {parseStrh} from './parse-strh';
 import type {RiffBox, RiffRegularBox} from './riff-box';
+import {parseStrf} from './strf';
 
 export const parseRiffBox = ({
 	iterator,
@@ -32,6 +33,10 @@ export const parseRiffBox = ({
 		return parseStrh({iterator, size});
 	}
 
+	if (id === 'strf') {
+		return parseStrf({iterator, size, boxes});
+	}
+
 	iterator.discard(size);
 
 	const box: RiffRegularBox = {

packages/media-parser/src/boxes/riff/riff-box.ts

@@ -51,6 +51,32 @@ export type StrhBox = {
 	language: number;
 };
 
+export type StrfBoxVideo = {
+	type: 'strf-box-video';
+	biSize: number;
+	width: number;
+	height: number;
+	planes: number;
+	bitCount: number;
+	compression: string;
+	sizeImage: number;
+	xPelsPerMeter: number;
+	yPelsPerMeter: number;
+	clrUsed: number;
+	clrImportant: number;
+};
+
+export type StrfBoxAudio = {
+	type: 'strf-box-audio';
+	formatTag: number;
+	numberOfChannels: number;
+	sampleRate: number;
+	avgBytesPerSecond: number;
+	blockAlign: number;
+	bitsPerSample: number;
+	cbSize: number;
+};
+
 export type RiffHeader = {
 	type: 'riff-header';
 	fileSize: number;
@@ -63,4 +89,6 @@ export type RiffBox =
 	| RiffHeader
 	| ListBox
 	| AvihBox
-	| StrhBox;
+	| StrhBox
+	| StrfBoxVideo
+	| StrfBoxAudio;

packages/media-parser/src/boxes/riff/strf.ts

@@ -0,0 +1,95 @@
+import type {BufferIterator} from '../../buffer-iterator';
+import type {RiffBox} from './riff-box';
+
+const parseStrfAudio = ({
+	iterator,
+	size,
+}: {
+	iterator: BufferIterator;
+	size: number;
+}): RiffBox => {
+	const box = iterator.startBox(size);
+	const formatTag = iterator.getUint16Le();
+	const numberOfChannels = iterator.getUint16Le();
+	const samplesPerSec = iterator.getUint32Le();
+	const avgBytesPerSec = iterator.getUint32Le();
+	const blockAlign = iterator.getUint16Le();
+	const bitsPerSample = iterator.getUint16Le();
+	const cbSize = iterator.getUint16Le();
+
+	box.expectNoMoreBytes();
+
+	return {
+		type: 'strf-box-audio',
+		avgBytesPerSecond: avgBytesPerSec,
+		bitsPerSample,
+		blockAlign,
+		cbSize,
+		formatTag,
+		numberOfChannels,
+		sampleRate: samplesPerSec,
+	};
+};
+
+const parseStrfVideo = ({
+	iterator,
+	size,
+}: {
+	iterator: BufferIterator;
+	size: number;
+}): RiffBox => {
+	const box = iterator.startBox(size);
+	const biSize = iterator.getUint32Le();
+	const width = iterator.getInt32Le();
+	const height = iterator.getInt32Le();
+	const planes = iterator.getUint16Le();
+	const bitCount = iterator.getUint16Le();
+	const compression = iterator.getByteString(4);
+	const sizeImage = iterator.getUint32Le();
+	const xPelsPerMeter = iterator.getInt32Le();
+	const yPelsPerMeter = iterator.getInt32Le();
+	const clrUsed = iterator.getUint32Le();
+	const clrImportant = iterator.getUint32Le();
+
+	box.expectNoMoreBytes();
+
+	return {
+		type: 'strf-box-video',
+		biSize,
+		bitCount,
+		clrImportant,
+		clrUsed,
+		compression,
+		height,
+		planes,
+		sizeImage,
+		width,
+		xPelsPerMeter,
+		yPelsPerMeter,
+	};
+};
+
+export const parseStrf = ({
+	iterator,
+	size,
+	boxes,
+}: {
+	iterator: BufferIterator;
+	size: number;
+	boxes: RiffBox[];
+}): RiffBox => {
+	const strh = boxes.find((b) => b.type === 'strh-box');
+	if (!strh) {
+		throw new Error('strh box not found');
+	}
+
+	if (strh.fccType === 'vids') {
+		return parseStrfVideo({iterator, size});
+	}
+
+	if (strh.fccType === 'auds') {
+		return parseStrfAudio({iterator, size});
+	}
+
+	throw new Error(`Unsupported fccType: ${strh.fccType}`);
+};

packages/media-parser/src/test/parse-avi-file.test.ts

@@ -51,9 +51,18 @@ test('AVI file', async () => {
 							language: 0,
 						},
 						{
-							id: 'strf',
-							size: 40,
-							type: 'riff-box',
+							biSize: 40,
+							bitCount: 24,
+							clrImportant: 0,
+							clrUsed: 0,
+							compression: 'H264',
+							height: 270,
+							planes: 1,
+							sizeImage: 388800,
+							type: 'strf-box-video',
+							width: 480,
+							xPelsPerMeter: 0,
+							yPelsPerMeter: 0,
 						},
 						{
 							id: 'JUNK',
@@ -88,9 +97,14 @@ test('AVI file', async () => {
 							language: 0,
 						},
 						{
-							id: 'strf',
-							size: 18,
-							type: 'riff-box',
+							avgBytesPerSecond: 17454,
+							bitsPerSample: 16,
+							blockAlign: 1536,
+							cbSize: 0,
+							formatTag: 255,
+							numberOfChannels: 2,
+							sampleRate: 48000,
+							type: 'strf-box-audio',
 						},
 						{
 							id: 'JUNK',