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我試圖從rtsp服務器解碼h264流並在iPhone上呈現它。FFmpeg不解碼h264流
我找到了一些圖書館並閱讀了一些關於它的文章。
圖書館來自iPhone的dropCam，名爲RTSPClient和DecoderWrapper。
但我不能用DecodeWrapper在ffmpeg上解碼幀數據。
這是我的代碼。
VideoViewer.m
- (void)didReceiveFrame:(NSData*)frameData presentationTime:(NSDate*)presentationTime
{
[VideoDecoder staticInitialize];
mConverter = [[VideoDecoder alloc] initWithCodec:kVCT_H264 colorSpace:kVCS_RGBA32 width:320 height:240 privateData:nil];
[mConverter decodeFrame:frameData];
if ([mConverter isFrameReady]) {
UIImage *imageData =[mConverter getDecodedFrame];
if (imageData) {
[mVideoView setImage:imageData];
NSLog(@"decoded!");
}
}
}
---VideoDecoder.m---
- (id)initWithCodec:(enum VideoCodecType)codecType
colorSpace:(enum VideoColorSpace)colorSpace
width:(int)width
height:(int)height
privateData:(NSData*)privateData {
if(self = [super init]) {
codec = avcodec_find_decoder(CODEC_ID_H264);
codecCtx = avcodec_alloc_context();
// Note: for H.264 RTSP streams, the width and height are usually not specified (width and height are 0).
// These fields will become filled in once the first frame is decoded and the SPS is processed.
codecCtx->width = width;
codecCtx->height = height;
codecCtx->extradata = av_malloc([privateData length]);
codecCtx->extradata_size = [privateData length];
[privateData getBytes:codecCtx->extradata length:codecCtx->extradata_size];
codecCtx->pix_fmt = PIX_FMT_RGBA;
#ifdef SHOW_DEBUG_MV
codecCtx->debug_mv = 0xFF;
#endif
srcFrame = avcodec_alloc_frame();
dstFrame = avcodec_alloc_frame();
int res = avcodec_open(codecCtx, codec);
if (res < 0)
{
NSLog(@"Failed to initialize decoder");
}
}
return self;
}
- (void)decodeFrame:(NSData*)frameData {
AVPacket packet = {0};
packet.data = (uint8_t*)[frameData bytes];
packet.size = [frameData length];
int frameFinished=0;
NSLog(@"Packet size===>%d",packet.size);
// Is this a packet from the video stream?
if(packet.stream_index==0)
{
int res = avcodec_decode_video2(codecCtx, srcFrame, &frameFinished, &packet);
NSLog(@"Res value===>%d",res);
NSLog(@"frame data===>%d",(int)srcFrame->data);
if (res < 0)
{
NSLog(@"Failed to decode frame");
}
}
else
{
NSLog(@"No video stream found");
}
// Need to delay initializing the output buffers because we don't know the dimensions until we decode the first frame.
if (!outputInit) {
if (codecCtx->width > 0 && codecCtx->height > 0) {
#ifdef _DEBUG
NSLog(@"Initializing decoder with frame size of: %dx%d", codecCtx->width, codecCtx->height);
#endif
outputBufLen = avpicture_get_size(PIX_FMT_RGBA, codecCtx->width, codecCtx->height);
outputBuf = av_malloc(outputBufLen);
avpicture_fill((AVPicture*)dstFrame, outputBuf, PIX_FMT_RGBA, codecCtx->width, codecCtx->height);
convertCtx = sws_getContext(codecCtx->width, codecCtx->height, codecCtx->pix_fmt, codecCtx->width,
codecCtx->height, PIX_FMT_RGBA, SWS_FAST_BILINEAR, NULL, NULL, NULL);
outputInit = YES;
frameFinished=1;
}
else {
NSLog(@"Could not get video output dimensions");
}
}
if (frameFinished)
frameReady = YES;
}
控制檯顯示如下。
2011-05-16 20:16:04.223 RTSPTest1[41226:207] Packet size===>359
[h264 @ 0x5815c00] no frame!
2011-05-16 20:16:04.223 RTSPTest1[41226:207] Res value===>-1
2011-05-16 20:16:04.224 RTSPTest1[41226:207] frame data===>101791200
2011-05-16 20:16:04.224 RTSPTest1[41226:207] Failed to decode frame
2011-05-16 20:16:04.225 RTSPTest1[41226:207] decoded!
2011-05-16 20:16:04.226 RTSPTest1[41226:207] Packet size===>424
[h264 @ 0x5017c00] no frame!
2011-05-16 20:16:04.226 RTSPTest1[41226:207] Res value===>-1
2011-05-16 20:16:04.227 RTSPTest1[41226:207] frame data===>81002704
2011-05-16 20:16:04.227 RTSPTest1[41226:207] Failed to decode frame
2011-05-16 20:16:04.228 RTSPTest1[41226:207] decoded!
2011-05-16 20:16:04.229 RTSPTest1[41226:207] Packet size===>424
[h264 @ 0x581d000] no frame!
2011-05-16 20:16:04.229 RTSPTest1[41226:207] Res value===>-1
2011-05-16 20:16:04.230 RTSPTest1[41226:207] frame data===>101791616
2011-05-16 20:16:04.230 RTSPTest1[41226:207] Failed to decode frame
2011-05-16 20:16:04.231 RTSPTest1[41226:207] decoded!
. . . . .
但模擬器什麼都沒顯示。
我的代碼有什麼問題。
幫我解決這個問題。
感謝您的回答。