New upstream version 26.1.0+dfsg1

plugins/mac-virtualcam/src/dal-plugin/CMSampleBufferUtils.mm

@@ -0,0 +1,187 @@
+//
+//  CMSampleBufferUtils.m
+//  dal-plugin
+//
+//  Created by John Boiles  on 5/8/20.
+//
+
+#import "CMSampleBufferUtils.h"
+
+#include "Logging.h"
+
+/*!
+CMSampleBufferCreateFromData
+
+Creates a CMSampleBuffer by copying bytes from NSData into a CVPixelBuffer.
+*/
+OSStatus CMSampleBufferCreateFromData(NSSize size,
+				      CMSampleTimingInfo timingInfo,
+				      UInt64 sequenceNumber, NSData *data,
+				      CMSampleBufferRef *sampleBuffer)
+{
+	OSStatus err = noErr;
+
+	// Create an empty pixel buffer
+	CVPixelBufferRef pixelBuffer;
+	err = CVPixelBufferCreate(kCFAllocatorDefault, size.width, size.height,
+				  kCVPixelFormatType_422YpCbCr8, nil,
+				  &pixelBuffer);
+	if (err != noErr) {
+		DLog(@"CVPixelBufferCreate err %d", err);
+		return err;
+	}
+
+	// Generate the video format description from that pixel buffer
+	CMFormatDescriptionRef format;
+	err = CMVideoFormatDescriptionCreateForImageBuffer(NULL, pixelBuffer,
+							   &format);
+	if (err != noErr) {
+		DLog(@"CMVideoFormatDescriptionCreateForImageBuffer err %d",
+		     err);
+		return err;
+	}
+
+	// Copy memory into the pixel buffer
+	CVPixelBufferLockBaseAddress(pixelBuffer, 0);
+	uint8_t *dest =
+		(uint8_t *)CVPixelBufferGetBaseAddressOfPlane(pixelBuffer, 0);
+	uint8_t *src = (uint8_t *)data.bytes;
+
+	size_t destBytesPerRow =
+		CVPixelBufferGetBytesPerRowOfPlane(pixelBuffer, 0);
+	size_t srcBytesPerRow = size.width * 2;
+
+	// Sometimes CVPixelBufferCreate will create a pixelbuffer that's a different
+	// size than necessary to hold the frame (probably for some optimization reason).
+	// If that is the case this will do a row-by-row copy into the buffer.
+	if (destBytesPerRow == srcBytesPerRow) {
+		memcpy(dest, src, data.length);
+	} else {
+		for (int line = 0; line < size.height; line++) {
+			memcpy(dest, src, srcBytesPerRow);
+			src += srcBytesPerRow;
+			dest += destBytesPerRow;
+		}
+	}
+
+	CVPixelBufferUnlockBaseAddress(pixelBuffer, 0);
+
+	err = CMIOSampleBufferCreateForImageBuffer(kCFAllocatorDefault,
+						   pixelBuffer, format,
+						   &timingInfo, sequenceNumber,
+						   0, sampleBuffer);
+	CFRelease(format);
+	CFRelease(pixelBuffer);
+
+	if (err != noErr) {
+		DLog(@"CMIOSampleBufferCreateForImageBuffer err %d", err);
+		return err;
+	}
+
+	return noErr;
+}
+
+static void releaseNSData(void *o, void *block, size_t size)
+{
+	NSData *data = (__bridge_transfer NSData *)o;
+	data = nil; // Assuming ARC is enabled
+}
+
+// From https://stackoverflow.com/questions/26158253/how-to-create-a-cmblockbufferref-from-nsdata
+OSStatus createReadonlyBlockBuffer(CMBlockBufferRef *result, NSData *data)
+{
+	CMBlockBufferCustomBlockSource blockSource = {
+		.version = kCMBlockBufferCustomBlockSourceVersion,
+		.AllocateBlock = NULL,
+		.FreeBlock = &releaseNSData,
+		.refCon = (__bridge_retained void *)data,
+	};
+	return CMBlockBufferCreateWithMemoryBlock(NULL, (void *)data.bytes,
+						  data.length, NULL,
+						  &blockSource, 0, data.length,
+						  0, result);
+}
+
+/*!
+ CMSampleBufferCreateFromDataNoCopy
+
+ Creates a CMSampleBuffer by using the bytes directly from NSData (without copying them).
+ Seems to mostly work but does not work at full resolution in OBS for some reason (which prevents loopback testing).
+ */
+OSStatus CMSampleBufferCreateFromDataNoCopy(NSSize size,
+					    CMSampleTimingInfo timingInfo,
+					    UInt64 sequenceNumber, NSData *data,
+					    CMSampleBufferRef *sampleBuffer)
+{
+	OSStatus err = noErr;
+
+	CMBlockBufferRef dataBuffer;
+	createReadonlyBlockBuffer(&dataBuffer, data);
+
+	// Magic format properties snagged from https://github.com/lvsti/CoreMediaIO-DAL-Example/blob/0392cbf27ed33425a1a5bd9f495b2ccec8f20501/Sources/Extras/CoreMediaIO/DeviceAbstractionLayer/Devices/Sample/PlugIn/CMIO_DP_Sample_Stream.cpp#L830
+	NSDictionary *extensions = @{
+		@"com.apple.cmio.format_extension.video.only_has_i_frames":
+			@YES,
+		(__bridge NSString *)
+		kCMFormatDescriptionExtension_FieldCount: @1,
+		(__bridge NSString *)
+		kCMFormatDescriptionExtension_ColorPrimaries:
+			(__bridge NSString *)
+				kCMFormatDescriptionColorPrimaries_SMPTE_C,
+		(__bridge NSString *)
+		kCMFormatDescriptionExtension_TransferFunction: (
+			__bridge NSString *)
+			kCMFormatDescriptionTransferFunction_ITU_R_709_2,
+		(__bridge NSString *)
+		kCMFormatDescriptionExtension_YCbCrMatrix: (__bridge NSString *)
+			kCMFormatDescriptionYCbCrMatrix_ITU_R_601_4,
+		(__bridge NSString *)
+		kCMFormatDescriptionExtension_BytesPerRow: @(size.width * 2),
+		(__bridge NSString *)kCMFormatDescriptionExtension_FormatName:
+			@"Component Video - CCIR-601 uyvy",
+		(__bridge NSString *)kCMFormatDescriptionExtension_Version: @2,
+	};
+
+	CMFormatDescriptionRef format;
+	err = CMVideoFormatDescriptionCreate(
+		NULL, kCMVideoCodecType_422YpCbCr8, size.width, size.height,
+		(__bridge CFDictionaryRef)extensions, &format);
+	if (err != noErr) {
+		DLog(@"CMVideoFormatDescriptionCreate err %d", err);
+		return err;
+	}
+
+	size_t dataSize = data.length;
+	err = CMIOSampleBufferCreate(kCFAllocatorDefault, dataBuffer, format, 1,
+				     1, &timingInfo, 1, &dataSize,
+				     sequenceNumber, 0, sampleBuffer);
+	CFRelease(format);
+	CFRelease(dataBuffer);
+
+	if (err != noErr) {
+		DLog(@"CMIOSampleBufferCreate err %d", err);
+		return err;
+	}
+
+	return noErr;
+}
+
+CMSampleTimingInfo CMSampleTimingInfoForTimestamp(uint64_t timestampNanos,
+						  uint32_t fpsNumerator,
+						  uint32_t fpsDenominator)
+{
+	// The timing here is quite important. For frames to be delivered correctly and successfully be recorded by apps
+	// like QuickTime Player, we need to be accurate in both our timestamps _and_ have a sensible scale. Using large
+	// timestamps and scales like mach_absolute_time() and NSEC_PER_SEC will work for display, but will error out
+	// when trying to record.
+	//
+	// 600 is a commmon default in Apple's docs https://developer.apple.com/documentation/avfoundation/avmutablemovie/1390622-timescale
+	CMTimeScale scale = 600;
+	CMSampleTimingInfo timing;
+	timing.duration =
+		CMTimeMake(fpsDenominator * scale, fpsNumerator * scale);
+	timing.presentationTimeStamp = CMTimeMake(
+		(timestampNanos / (double)NSEC_PER_SEC) * scale, scale);
+	timing.decodeTimeStamp = kCMTimeInvalid;
+	return timing;
+}