Fixed detecting frame borders in MPEG-2 streams that have "bottom fields" or varying GOP structures

This commit is contained in:
Klaus Schmidinger
2014-01-25 14:37:05 +01:00
parent 6bd94489de
commit dd95f4ed61
3 changed files with 33 additions and 5 deletions

30
remux.c
View File

@@ -4,7 +4,7 @@
* See the main source file 'vdr.c' for copyright information and
* how to reach the author.
*
* $Id: remux.c 2.75 2013/03/03 10:37:58 kls Exp $
* $Id: remux.c 2.75.1.1 2014/01/25 14:37:05 kls Exp $
*/
#include "remux.h"
@@ -1004,6 +1004,7 @@ protected:
bool debug;
bool newFrame;
bool independentFrame;
int iFrameTemporalReferenceOffset;
public:
cFrameParser(void);
virtual ~cFrameParser() {};
@@ -1017,6 +1018,7 @@ public:
void SetDebug(bool Debug) { debug = Debug; }
bool NewFrame(void) { return newFrame; }
bool IndependentFrame(void) { return independentFrame; }
int IFrameTemporalReferenceOffset(void) { return iFrameTemporalReferenceOffset; }
};
cFrameParser::cFrameParser(void)
@@ -1024,6 +1026,7 @@ cFrameParser::cFrameParser(void)
debug = true;
newFrame = false;
independentFrame = false;
iFrameTemporalReferenceOffset = 0;
}
// --- cAudioParser ----------------------------------------------------------
@@ -1056,6 +1059,7 @@ class cMpeg2Parser : public cFrameParser {
private:
uint32_t scanner;
bool seenIndependentFrame;
int lastIFrameTemporalReference;
public:
cMpeg2Parser(void);
virtual int Parse(const uchar *Data, int Length, int Pid);
@@ -1065,6 +1069,7 @@ cMpeg2Parser::cMpeg2Parser(void)
{
scanner = EMPTY_SCANNER;
seenIndependentFrame = false;
lastIFrameTemporalReference = -1; // invalid
}
int cMpeg2Parser::Parse(const uchar *Data, int Length, int Pid)
@@ -1089,10 +1094,25 @@ int cMpeg2Parser::Parse(const uchar *Data, int Length, int Pid)
scanner = OldScanner;
return tsPayload.Used() - TS_SIZE;
}
uchar b1 = tsPayload.GetByte();
uchar b2 = tsPayload.GetByte();
int TemporalReference = (b1 << 2 ) + ((b2 & 0xC0) >> 6);
uchar FrameType = (b2 >> 3) & 0x07;
if (tsPayload.Find(0x000001B5)) { // Extension start code
if (((tsPayload.GetByte() & 0xF0) >> 4) == 0x08) { // Picture coding extension
tsPayload.GetByte();
uchar PictureStructure = tsPayload.GetByte() & 0x03;
if (PictureStructure == 0x02) // bottom field
break;
}
}
newFrame = true;
tsPayload.GetByte();
uchar FrameType = (tsPayload.GetByte() >> 3) & 0x07;
independentFrame = FrameType == 1; // I-Frame
if (independentFrame) {
if (lastIFrameTemporalReference >= 0)
iFrameTemporalReferenceOffset = TemporalReference - lastIFrameTemporalReference;
lastIFrameTemporalReference = TemporalReference;
}
if (debug) {
seenIndependentFrame |= independentFrame;
if (seenIndependentFrame) {
@@ -1457,7 +1477,7 @@ int cFrameDetector::Analyze(const uchar *Data, int Length)
for (int i = 0; i < numPtsValues; i++)
ptsValues[i] = ptsValues[i + 1] - ptsValues[i];
qsort(ptsValues, numPtsValues, sizeof(uint32_t), CmpUint32);
uint32_t Delta = ptsValues[0] / framesPerPayloadUnit;
uint32_t Delta = ptsValues[0] / (framesPerPayloadUnit + parser->IFrameTemporalReferenceOffset());
// determine frame info:
if (isVideo) {
if (abs(Delta - 3600) <= 1)
@@ -1475,7 +1495,7 @@ int cFrameDetector::Analyze(const uchar *Data, int Length)
}
else // audio
framesPerSecond = double(PTSTICKS) / Delta; // PTS of audio frames is always increasing
dbgframes("\nDelta = %d FPS = %5.2f FPPU = %d NF = %d\n", Delta, framesPerSecond, framesPerPayloadUnit, numPtsValues + 1);
dbgframes("\nDelta = %d FPS = %5.2f FPPU = %d NF = %d TRO = %d\n", Delta, framesPerSecond, framesPerPayloadUnit, numPtsValues + 1, parser->IFrameTemporalReferenceOffset());
synced = true;
parser->SetDebug(false);
}