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//
// CVImageDecorder.m
// Turkey
//
// Created by numa08 on 2018/05/10.
// Copyright © 2018年 numa08. All rights reserved.
//
#include <sys/types.h>
#include <sys/stat.h>
extern "C" {
#include <libavcodec/avcodec.h>
#include <libavfilter/avfilter.h>
#include <libavformat/avformat.h>
#include <libavutil/imgutils.h>
#include <libswscale/swscale.h>
}
#import <CoreML/CoreML.h>
#import <CoreVideo/CoreVideo.h>
#import <Foundation/Foundation.h>
#import <UIKit/UIKit.h>
#import "ImageDecoder.h"
@interface ImageDecoder()
{
dispatch_queue_t writeFifoQueue;
}
@property NSPipe *fifoPipe;
@property NSMutableArray *packetArray;
- (void)startCaptureThread;
- (void)captureInFFMpeg;
- (UIImage*)rgb24ToUIImage:(uint8_t*)pRgb width:(int)width height:(int)height wrap:(int)wrap;
@end
@implementation ImageDecoder
- (instancetype)init
{
self = [super init];
self.fifoPipe = [NSPipe pipe];
self.packetArray = [NSMutableArray array];
return self;
}
- (BOOL)open
{
writeFifoQueue = dispatch_queue_create("write_fifo", DISPATCH_QUEUE_SERIAL);
// 正しいフレーム情報をもった動画ファイルを読み込んで、
// avformat_find_stream_info を成功させる
dispatch_async(writeFifoQueue, ^{
NSString *p = [[NSBundle mainBundle] pathForResource:@"movie" ofType:@"mov"];
FILE *i_file = fopen(p.UTF8String, "r");
if (i_file == NULL) {
NSLog(@"failed fopen");
return;
}
int buffer_size = 10 * 1024;
char buff[buffer_size];
size_t size;
while (true) {
size = fread(buff, buffer_size, 1, i_file);
if (size == 0) {
break;
}
write(self.fifoPipe.fileHandleForWriting.fileDescriptor, buff, buffer_size);
}
});
[self startCaptureThread];
return YES;
}
- (void)onNewFrame:(NSData*)frame
{
dispatch_async(writeFifoQueue, ^{
[self.packetArray addObject:frame];
if (self.packetArray.count == 8) {
NSMutableData *packet = [NSMutableData data];
for (NSData *d in self.packetArray) {
[packet appendData:d];
}
[self.fifoPipe.fileHandleForWriting writeData:packet];
self.packetArray = [NSMutableArray array];
}
});
}
- (void)close
{
// close(self.fifoDescriptor);
}
-(void)startCaptureThread
{
dispatch_queue_t queue = dispatch_queue_create("capture", nil);
dispatch_async(queue, ^{
[self captureInFFMpeg];
});
}
- (void)captureInFFMpeg
{
av_register_all();
int fileDescriptor = self.fifoPipe.fileHandleForReading.fileDescriptor;
const char* file = [NSString stringWithFormat:@"pipe:%d", fileDescriptor].UTF8String;
AVInputFormat *input_format = av_find_input_format("h264");
AVFormatContext *format_context = avformat_alloc_context();
format_context->probesize = INT_MAX;
// format_context->max_analyze_duration = 20000000;
format_context->debug = 1;
AVDictionary *format_dictionary = NULL;
av_dict_set(&format_dictionary, "pixel_format", "yuv420p", 0);
av_dict_set(&format_dictionary, "video_size", "960x720", 0);
av_dict_set(&format_dictionary, "profile", "main", 0);
int ret;
ret = avformat_open_input(&format_context, file, input_format, &format_dictionary);
if (ret < 0) {
char buf[1024];
av_strerror(AVERROR(ret), buf, 1024);
NSLog(@"avformat_open_input failed %s", buf);
return;
}
ret = avformat_find_stream_info(format_context, &format_dictionary);
if (ret < 0) {
NSLog(@"avformat_find_stream_info failed: %08x", AVERROR(ret));
return;
}
av_dump_format(format_context, 0, file, 0);
int stream_index = av_find_best_stream(format_context, AVMEDIA_TYPE_VIDEO, -1, -1, NULL, 0);
if (stream_index < 0) {
NSLog(@"cound not find video stream");
return;
}
AVStream *stream = format_context->streams[stream_index];
// 読み込み用フレーム
AVFrame *source_frame = av_frame_alloc();
int source_width = stream->codecpar->width;
int source_height = stream->codecpar->height;
enum AVPixelFormat source_format = (AVPixelFormat)stream->codecpar->format;
// RGB 変換用フレーム
AVFrame *dest_frame = av_frame_alloc();
int dest_width = stream->codecpar->width;
int dest_height = stream->codecpar->height;
enum AVPixelFormat dest_format = AV_PIX_FMT_RGB24;
int dest_buffer_align = 32;
uint8_t *dest_buffer = (uint8_t*)av_malloc(av_image_get_buffer_size(dest_format, dest_width, dest_height, dest_buffer_align));
av_image_fill_arrays(dest_frame->data, dest_frame->linesize, dest_buffer, dest_format, dest_width, dest_height, dest_buffer_align);
SwsContext *sws_context = sws_getContext(source_width, source_height, source_format, dest_width, dest_height, dest_format, SWS_FAST_BILINEAR, NULL, NULL, NULL);
AVCodec *codec = avcodec_find_decoder(stream->codecpar->codec_id);
if (codec == NULL) {
NSLog(@"cound not find codec for id %d", stream->codecpar->codec_id);
return;
}
AVCodecContext *codec_context = avcodec_alloc_context3(codec);
if (codec_context == NULL) {
NSLog(@"avcodec_alloc_context3 failed");
return;
}
if (avcodec_parameters_to_context(codec_context, stream->codecpar) < 0) {
NSLog(@"avcodec_parameters_to_context failed");
return;
}
if (avcodec_open2(codec_context, codec, NULL) < 0) {
NSLog(@"avcodec_open2 failed");
return;
}
AVPacket packet;
while (av_read_frame(format_context, &packet) == 0) {
if (packet.stream_index == stream_index) {
int ret;
ret = avcodec_send_packet(codec_context, &packet);
if (ret != 0) {
char buf[1024];
av_strerror(AVERROR(ret), buf, 1024);
NSLog(@"avcodec_send_packet failed, %s", buf);
}
while (avcodec_receive_frame(codec_context, source_frame) == 0) {
sws_scale(sws_context, source_frame->data, source_frame->linesize, 0, source_height, dest_frame->data, dest_frame->linesize);
UIImage * image = [self rgb24ToUIImage:dest_frame->data[0] width:dest_width height:dest_height wrap:dest_frame->linesize[0]];
[self.delegate decoder:self didDecodeImage:image];
}
}
av_packet_unref(&packet);
}
NSLog(@"ok codec %d", stream->codecpar->codec_id);
}
- (UIImage*)rgb24ToUIImage:(uint8_t*)pRgb width:(int)width height:(int)height wrap:(int)wrap
{
// RGB24 -> RGBA32 pixelデータ転送。
uint8_t* pRgba = (uint8_t*)malloc(width * height * 4);
for (int y = 0; y < height; ++y) {
int si = y * wrap;
int di = y * width * 4;
for (int x = 0; x < width; ++x) {
pRgba[di + 0] = pRgb[si + 0];
pRgba[di + 1] = pRgb[si + 1];
pRgba[di + 2] = pRgb[si + 2];
pRgba[di + 3] = UINT8_MAX;
si += 3;
di += 4;
}
}
// UIImage作成。
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
CGContextRef ctx = CGBitmapContextCreate(pRgba, width, height, 8, width * 4, colorSpace, kCGImageAlphaPremultipliedLast);
CGImageRef cgimage = CGBitmapContextCreateImage(ctx);
UIImage* uiimage = [[UIImage alloc] initWithCGImage:cgimage];
CGImageRelease(cgimage);
CGContextRelease(ctx);
free(pRgba);
return uiimage;
}
@end
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