feat(video): add native AVC/HEVC and synchronized AAC MP4 streaming

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packages/video/src/containers/mp4_stream.zigmodified+18-0

Changes to packages/video/src/containers/mp4_stream.zig

		⋯299 linesShow the 299 lines above this hunk@@ -300,3 +300,21 @@ test "fragment sizes, offsets and 64-bit time are exact; sink failure poisons wr
300	300	try std.testing.expectError(error.DiskFull, writer.frame(&.{ 0, 0, 0, 1, 1 }, 0x100000001, 1, false));
301	301	try std.testing.expectError(error.WriterFailed, writer.frame(&.{ 0, 0, 0, 1, 1 }, 0x100000002, 1, false));
302	302	}
	303	+
	304	+/// CodecPrivate for Matroska, without the enclosing avcC/hvcC box header.
	305	+pub fn codecPrivate(codec: Codec, headers: []const u8, destination: []u8) ![]const u8 {
	306	+ var b: Buffer = .{};
	307	+ try config(&b, codec, headers);
	308	+ const data = b.slice()[8..];
	309	+ if (destination.len < data.len) return error.HeaderTooLarge;
	310	+ @memcpy(destination[0..data.len], data);
	311	+ return destination[0..data.len];
	312	+}
	313	+test "Matroska CodecPrivate reuses checked config and respects destination bounds" {
	314	+ const headers = [_]u8{ 0, 0, 0, 4, 0x67, 100, 0, 40, 0, 0, 0, 2, 0x68, 0x80 };
	315	+ var destination: [128]u8 = undefined;
	316	+ const data = try codecPrivate(.h264, &headers, &destination);
	317	+ try std.testing.expectEqualSlices(u8, &.{ 1, 100, 0, 40, 255, 225 }, data[0..6]);
	318	+ try std.testing.expectError(error.HeaderTooLarge, codecPrivate(.h264, &headers, destination[0..1]));
	319	+ try std.testing.expectError(error.MissingParameterSets, codecPrivate(.h264, &.{}, &destination));
	320	+}