//

// MediaUtils.m

// APIExample

//

// Created by Arlin on 2022/4/12.

// Copyright © 2022 Agora Corp. All rights reserved.

//

#import "MediaUtils.h"

#import <CoreImage/CoreImage.h>

@implementation MediaUtils

+ (CVPixelBufferRef)i420ToPixelBuffer:(void *)srcY srcU:(void *)srcU srcV:(void *)srcV width:(int)width height:(int)height {

int size = width * height * 3 / 2;

int yLength = width * height;

int uLength = yLength / 4;

if (srcY == NULL) {

return nil;

}

unsigned char *buf = (unsigned char *)malloc(size);

memcpy(buf, srcY, yLength);

memcpy(buf + yLength, srcU, uLength);

memcpy(buf + yLength + uLength, srcV, uLength);

unsigned char * NV12buf = (unsigned char *)malloc(size);

[self yuv420p_to_nv12:buf nv12:NV12buf width:width height:height];

free(buf);

int w = width;

int h = height;

NSDictionary *pixelAttributes = @{(NSString*)kCVPixelBufferIOSurfacePropertiesKey:@{}};

CVPixelBufferRef pixelBuffer = NULL;

CVReturn result = CVPixelBufferCreate(kCFAllocatorDefault,

w,

h,

kCVPixelFormatType_420YpCbCr8BiPlanarVideoRange,

(__bridge CFDictionaryRef)(pixelAttributes),

&pixelBuffer);

if (result != kCVReturnSuccess) {

NSLog(@"Unable to create cvpixelbuffer %d", result);

free(NV12buf);

return nil;

}

CVPixelBufferLockBaseAddress(pixelBuffer,0);

void *yDestPlane = CVPixelBufferGetBaseAddressOfPlane(pixelBuffer, 0);

// Here y_ch0 is Y-Plane of YUV(NV12) data.

unsigned char *y_ch0 = NV12buf;

unsigned char *y_ch1 = NV12buf + w * h;

memcpy(yDestPlane, y_ch0, w * h);

void *uvDestPlane = CVPixelBufferGetBaseAddressOfPlane(pixelBuffer, 1);

// Here y_ch1 is UV-Plane of YUV(NV12) data.

memcpy(uvDestPlane, y_ch1, w * h * 0.5);

CVPixelBufferUnlockBaseAddress(pixelBuffer, 0);

free(NV12buf);

return pixelBuffer;

}

+ (NSData *)dataFromPixelBuffer:(CVPixelBufferRef)pixelBuffer {

NSMutableData* YUVMutData;

CVPixelBufferLockBaseAddress(pixelBuffer, 0);

unsigned char* yBaseAddress = (unsigned char*)CVPixelBufferGetBaseAddressOfPlane(pixelBuffer, 0);

int32_t yBytesPerRow = (int32_t)CVPixelBufferGetBytesPerRowOfPlane(pixelBuffer, 0);

int32_t width __unused = (int32_t)CVPixelBufferGetWidth(pixelBuffer);

int32_t height = (int32_t)CVPixelBufferGetHeight(pixelBuffer);

int32_t yLength = yBytesPerRow*height;

YUVMutData = [NSMutableData dataWithBytes: yBaseAddress length: yLength];

unsigned char* uvBaseAddress = (unsigned char*)CVPixelBufferGetBaseAddressOfPlane(pixelBuffer, 1);

int32_t uvBytesPerRow = (int32_t)CVPixelBufferGetBytesPerRowOfPlane(pixelBuffer, 1);

int32_t uvLength = uvBytesPerRow*height/2;

NSMutableData* UVData = [NSMutableData dataWithBytes: uvBaseAddress length: uvLength];

[YUVMutData appendData:UVData];

NSData* YUVData = [NSData dataWithData:YUVMutData];

CVPixelBufferUnlockBaseAddress(pixelBuffer, 0);

return YUVData;

}

+ (UIImage *)i420ToImage:(void *)srcY srcU:(void *)srcU srcV:(void *)srcV width:(int)width height:(int)height {

int size = width * height * 3 / 2;

int yLength = width * height;

int uLength = yLength / 4;

unsigned char *buf = (unsigned char *)malloc(size);

memcpy(buf, srcY, yLength);

memcpy(buf + yLength, srcU, uLength);

memcpy(buf + yLength + uLength, srcV, uLength);

unsigned char * NV12buf = (unsigned char *)malloc(size);

[self yuv420p_to_nv12:buf nv12:NV12buf width:width height:height];

free(buf);

int w = width;

int h = height;

NSDictionary *pixelAttributes = @{(NSString*)kCVPixelBufferIOSurfacePropertiesKey:@{}};

CVPixelBufferRef pixelBuffer = NULL;

CVReturn result = CVPixelBufferCreate(kCFAllocatorDefault,

w,

h,

kCVPixelFormatType_420YpCbCr8BiPlanarVideoRange,

(__bridge CFDictionaryRef)(pixelAttributes),

&pixelBuffer);

if (result != kCVReturnSuccess) {

NSLog(@"Unable to create cvpixelbuffer %d", result);

free(NV12buf);

return nil;

}

CVPixelBufferLockBaseAddress(pixelBuffer,0);

void *yDestPlane = CVPixelBufferGetBaseAddressOfPlane(pixelBuffer, 0);

// Here y_ch0 is Y-Plane of YUV(NV12) data.

unsigned char *y_ch0 = NV12buf;

unsigned char *y_ch1 = NV12buf + w * h;

memcpy(yDestPlane, y_ch0, w * h);

void *uvDestPlane = CVPixelBufferGetBaseAddressOfPlane(pixelBuffer, 1);

// Here y_ch1 is UV-Plane of YUV(NV12) data.

memcpy(uvDestPlane, y_ch1, w * h * 0.5);

CVPixelBufferUnlockBaseAddress(pixelBuffer, 0);

// CIImage Conversion

CIImage *coreImage = [CIImage imageWithCVPixelBuffer:pixelBuffer];

CIContext *temporaryContext = [CIContext contextWithOptions:nil];

CGImageRef videoImage = [temporaryContext createCGImage:coreImage

fromRect:CGRectMake(0, 0, w, h)];

UIImage *finalImage = [[UIImage alloc] initWithCGImage:videoImage];

CVPixelBufferRelease(pixelBuffer);

CGImageRelease(videoImage);

free(NV12buf);

return finalImage;

}

+ (UIImage *)pixelBufferToImage: (CVPixelBufferRef)pixelBuffer {

size_t width = CVPixelBufferGetHeight(pixelBuffer);

size_t height = CVPixelBufferGetWidth(pixelBuffer);

CIImage *coreImage = [CIImage imageWithCVPixelBuffer:pixelBuffer];

CIContext *temporaryContext = [CIContext contextWithOptions:nil];

CGImageRef videoImage = [temporaryContext createCGImage:coreImage

fromRect:CGRectMake(0, 0, height, width)];

UIImage *finalImage = [[UIImage alloc] initWithCGImage:videoImage

scale:1.0

orientation:UIImageOrientationUp];

// CVPixelBufferRelease(pixelBuffer);

CGImageRelease(videoImage);

return finalImage;

}

static OSType inputPixelFormat(){

return kCVPixelFormatType_32BGRA;

}

static uint32_t bitmapInfoWithPixelFormatType(OSType inputPixelFormat, bool hasAlpha){

if (inputPixelFormat == kCVPixelFormatType_32BGRA) {

uint32_t bitmapInfo = kCGImageAlphaPremultipliedFirst | kCGBitmapByteOrder32Host;

if (!hasAlpha) {

bitmapInfo = kCGImageAlphaNoneSkipFirst | kCGBitmapByteOrder32Host;

}

return bitmapInfo;

}else if (inputPixelFormat == kCVPixelFormatType_32ARGB) {

uint32_t bitmapInfo = kCGImageAlphaPremultipliedFirst | kCGBitmapByteOrder32Big;

return bitmapInfo;

}else{

NSLog(@"不支持此格式");

return 0;

}

}

// alpha的判断

BOOL CGImageRefContainsAlpha(CGImageRef imageRef) {

if (!imageRef) {

return NO;

}

CGImageAlphaInfo alphaInfo = CGImageGetAlphaInfo(imageRef);

BOOL hasAlpha = !(alphaInfo == kCGImageAlphaNone ||

alphaInfo == kCGImageAlphaNoneSkipFirst ||

alphaInfo == kCGImageAlphaNoneSkipLast);

return hasAlpha;

}

+ (CVPixelBufferRef)CVPixelBufferRefFromUiImage:(UIImage *)img {

CGSize size = img.size;

if (size.width <= 0 || size.height <= 0) {

return nil;

}

CGImageRef image = [img CGImage];

BOOL hasAlpha = CGImageRefContainsAlpha(image);

CFDictionaryRef empty = CFDictionaryCreate(kCFAllocatorDefault, NULL, NULL, 0, &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks);

NSDictionary *options = [NSDictionary dictionaryWithObjectsAndKeys:

[NSNumber numberWithBool:YES], kCVPixelBufferCGImageCompatibilityKey,

[NSNumber numberWithBool:YES], kCVPixelBufferCGBitmapContextCompatibilityKey,

empty, kCVPixelBufferIOSurfacePropertiesKey,

nil];

CVPixelBufferRef pxbuffer = NULL;

CVReturn status = CVPixelBufferCreate(kCFAllocatorDefault, size.width, size.height, inputPixelFormat(), (__bridge CFDictionaryRef) options, &pxbuffer);

NSParameterAssert(status == kCVReturnSuccess && pxbuffer != NULL);

CVPixelBufferLockBaseAddress(pxbuffer, 0);

void *pxdata = CVPixelBufferGetBaseAddress(pxbuffer);

NSParameterAssert(pxdata != NULL);

CGColorSpaceRef rgbColorSpace = CGColorSpaceCreateDeviceRGB();

uint32_t bitmapInfo = bitmapInfoWithPixelFormatType(inputPixelFormat(), (bool)hasAlpha);

CGContextRef context = CGBitmapContextCreate(pxdata, size.width, size.height, 8, CVPixelBufferGetBytesPerRow(pxbuffer), rgbColorSpace, bitmapInfo);

NSParameterAssert(context);

CGContextDrawImage(context, CGRectMake(0, 0, CGImageGetWidth(image), CGImageGetHeight(image)), image);

CVPixelBufferUnlockBaseAddress(pxbuffer, 0);

CGColorSpaceRelease(rgbColorSpace);

CGContextRelease(context);

return pxbuffer;

}

+ (void)yuv420p_to_nv12:(unsigned char*)yuv420p nv12:(unsigned char*)nv12 width:(int)width height:(int)height {

int i, j;

int y_size = width * height;

unsigned char* y = yuv420p;

unsigned char* u = yuv420p + y_size;

unsigned char* v = yuv420p + y_size * 5 / 4;

unsigned char* y_tmp = nv12;

unsigned char* uv_tmp = nv12 + y_size;

memcpy(y_tmp, y, y_size);

for (j = 0, i = 0; j < y_size * 0.5; j += 2, i++) {

uv_tmp[j] = u[i];

uv_tmp[j+1] = v[i];

}

}

@end