mpeg.c

linux下将各类格式图片转换工具

        bbP = Bitio_New(NULL);
    else {
        const char * fileName;

        asprintfN(&fileName, "%s.frame.%d", outputFileName, frameNumber);

        bbP = Bitio_New_Filename(fileName);

        strfree(fileName);
    }
    return bbP;
}



static void
getBFrame(int                  const frameNum,
          struct inputSource * const inputSourceP,
          MpegFrame *          const pastRefFrameP,
          boolean              const childProcess,
          boolean              const remoteIO,
          MpegFrame **         const bFramePP,
          int *                const IOtimeP,
          unsigned int *       const framesReadP) {
/*----------------------------------------------------------------------------
   Get Frame 'frameNum', which is a B frame related to previous reference
   frame 'pastRefFrameP'.  Return it as *bFramePP.

   We have various ways of getting the frame, corresponding to the
   multitude of modes in which Ppmtompeg works.
-----------------------------------------------------------------------------*/
    if (!inputSourceP->stdinUsed) {
        time_t tempTimeStart, tempTimeEnd;
        MpegFrame * bFrameP;

        bFrameP = Frame_New(frameNum, 'b');

        time(&tempTimeStart);

        ReadNthFrame(inputSourceP, frameNum, remoteIO, childProcess,
                     separateConversion, slaveConversion, inputConversion,
                     bFrameP);

        time(&tempTimeEnd);
        *IOtimeP += (tempTimeEnd-tempTimeStart);

        ++(*framesReadP);
        *bFramePP = bFrameP;
    } else {
        /* As the frame input is serial, we can't read the B frame now.
           Rather, Caller has already read it and chained it to 
           the previous reference frame.  So we get that copy now.
        */
        *bFramePP = pastRefFrameP->next;
        pastRefFrameP->next = (*bFramePP)->next;  /* unlink from list */
    }
}



static void
processBFrames(MpegFrame *          const pastRefFrameP,
               MpegFrame *          const futureRefFrameP,
               int                  const realStart,
               int                  const realEnd,
               struct inputSource * const inputSourceP,
               boolean              const remoteIo,
               boolean              const childProcess,
               int *                const IOtimeP,
               BitBucket *          const wholeStreamBbP,
               const char *         const outputFileName,
               unsigned int *       const framesReadP,
               unsigned int *       const framesOutputP,
               int *                const currentGopP) {
/*----------------------------------------------------------------------------
   Process the B frames that go between 'pastRefFrameP' and
   'futureRefFrame' in the movie (but go after 'futureRefFrameP' in the
   MPEG stream, so reader doesn't have to read ahead).

   Remember that a B frame is one which is described by data in the
   MPEG stream that describes the frame with respect to a frame somewhere
   before it, and a frame somewhere after it (i.e. reference frames).

   But do only those B frames whose frame numbers are within the range
   'realStart' through 'realEnd'.
-----------------------------------------------------------------------------*/
    boolean const separateFiles = (wholeStreamBbP == NULL);
    unsigned int const firstBFrameNum = pastRefFrameP->id + 1;

    int frameNum;

    assert(pastRefFrameP != NULL);
    assert(futureRefFrameP != NULL);
    
    for (frameNum = MAX(realStart, firstBFrameNum); 
         frameNum < MIN(realEnd, futureRefFrameP->id); 
         ++frameNum) {

        MpegFrame * bFrame;
        BitBucket * bbP;

        getBFrame(frameNum, inputSourceP, pastRefFrameP, childProcess, 
                  remoteIO,
                  &bFrame, IOtimeP, framesReadP);

        if (separateFiles)
            bbP = bitioNew(outputFileName, bFrame->id, remoteIO);
        else
            bbP = wholeStreamBbP;

        GenBFrame(bbP, bFrame, pastRefFrameP, futureRefFrameP);
        ++(*framesOutputP);

        if (separateFiles) {
            if (remoteIO)
                SendRemoteFrame(bFrame->id, bbP);
            else {
                Bitio_Flush(bbP);
                Bitio_Close(bbP);
            }
        }

        /* free this B frame right away */
        Frame_Free(bFrame);

        numB--;
        timeMask &= 0x3;
        ShowRemainingTime(childProcess);

        ++(*currentGopP);
        IncrementTCTime();
    }
}



static void
processRefFrame(MpegFrame *    const frameP, 
                BitBucket *    const bb_arg,
                int            const lastFrame,
                int            const realStart,
                int            const realEnd,
                MpegFrame *    const pastRefFrameP,
                boolean        const childProcess,
                const char *   const outputFileName,
                unsigned int * const framesReadP,
                unsigned int * const framesOutputP) {
/*----------------------------------------------------------------------------
   Process an I or P frame.  Encode and output it.

   But only if its frame number is within the range 'realStart'
   through 'realEnd'.
-----------------------------------------------------------------------------*/
    if (frameP->id >= realStart && frameP->id <= realEnd) {
        boolean separateFiles;
        BitBucket * bb;
  
        separateFiles = (bb_arg == NULL);
  
        if ( separateFiles )
            bb = bitioNew(outputFileName, frameP->id, remoteIO);
        else
            bb = bb_arg;
  
        /* first, output this reference frame */
        switch (frameP->type) {
        case TYPE_IFRAME:
            outputIFrame(frameP, bb, realStart, realEnd, pastRefFrameP, 
                         separateFiles);
            break;
        case TYPE_PFRAME:
            outputPFrame(frameP, bb, realStart, realEnd, pastRefFrameP);
            ShowRemainingTime(childProcess);
            break;
        default:
            pm_error("INTERNAL ERROR: non-reference frame passed to "
                     "ProcessRefFrame()");
        }  
        
        ++(*framesOutputP);
        
        finishFrameOutput(frameP, bb, separateFiles, referenceFrame,
                          childProcess, remoteIO);
    }
}



static void
countFrames(unsigned int const firstFrame,
            unsigned int const lastFrame,
            boolean      const stdinUsed,
            int *        const numIP,
            int *        const numPP,
            int *        const numBP,
            int *        const timeMaskP,
            boolean *    const frameCountsUnknownP) {
/*----------------------------------------------------------------------------
  Count number of I, P, and B frames
-----------------------------------------------------------------------------*/
    unsigned int numI, numP, numB;
    unsigned int timeMask;
            
    numI = 0; numP = 0; numB = 0;
    timeMask = 0;
    if (stdinUsed) {
        numI = numP = numB = MAXINT/4;
        *frameCountsUnknownP = TRUE;
    } else {
        unsigned int i;
        for (i = firstFrame; i <= lastFrame; ++i) {
            char const frameType = FType_Type(i);
            switch(frameType) {
            case 'i':        numI++;            timeMask |= 0x1;    break;
            case 'p':        numP++;            timeMask |= 0x2;    break;
            case 'b':        numB++;            timeMask |= 0x4;    break;
            }
        }
        *frameCountsUnknownP = FALSE;
    }

    *numIP     = numI;
    *numPP     = numP;
    *numBP     = numB;
    *timeMaskP = timeMask;
    *frameCountsUnknownP = frameCountsUnknown;
}



static void
readAndSaveFrame(struct inputSource * const inputSourceP,
                 unsigned int         const frameNumber,
                 char                 const frameType,
                 const char *         const inputConversion,
                 MpegFrame *          const pastRefFrameP,
                 unsigned int *       const framesReadP,
                 int *                const ioTimeP) {
/*----------------------------------------------------------------------------
   Read the next frame from Standard Input and add it to the linked list
   at *pastRefFrameP.  Assume it is Frame Number 'frameNumber' and is of
   type 'frameType'.
   
   Add the time it took to read it, in seconds, to *iotimeP.
-----------------------------------------------------------------------------*/

    /* This really should be part of ReadNthFrame.  The frame should be chained
       to the input object, not the past reference frame.
    */
       
    MpegFrame * p;
    MpegFrame * frameP;
    time_t ioTimeStart, ioTimeEnd;
    
    time(&ioTimeStart);

    frameP = Frame_New(frameNumber, frameType);
    ReadFrame(frameP, inputSourceP, frameNumber, inputConversion);
    
    ++(*framesReadP);
    
    time(&ioTimeEnd);
    *ioTimeP += (ioTimeEnd - ioTimeStart);

    /* Add the B frame to the end of the queue of B-frames 
       for later encoding.
    */
    assert(pastRefFrameP != NULL);
    
    p = pastRefFrameP;
    while (p->next != NULL)
        p = p->next;
    p->next = frameP;
}



static void
doFirstFrameStuff(enum frameContext const context,
                  const char *      const userDataFileName,
                  BitBucket *       const bb,
                  int               const fsize_x,
                  int               const fsize_y,
                  int               const aspectRatio,
                  int               const frameRate,
                  int32             const qtable[],
                  int32             const niqtable[],
                  unsigned int *    const inputFrameBitsP) {
/*----------------------------------------------------------------------------
   Do stuff we have to do after reading the first frame in a sequence
   of frames requested of GenMPEGStream().
-----------------------------------------------------------------------------*/
    *inputFrameBitsP = 24*Fsize_x*Fsize_y;
    SetBlocksPerSlice();
          
    if (context == CONTEXT_WHOLESTREAM) {
        int32 const bitstreamMode = getRateMode();
        char * userData;
        unsigned int userDataSize;

        assert(bb != NULL);

        DBG_PRINT(("Generating sequence header\n"));
        if (bitstreamMode == FIXED_RATE) {
            bit_rate = getBitRate();
            buf_size = getBufferSize();
        } else {
            bit_rate = -1;
            buf_size = -1;
        }
        
        if (strlen(userDataFileName) != 0) {
            struct stat statbuf;
            FILE *fp;
          
            stat(userDataFileName,&statbuf);
            userDataSize = statbuf.st_size;
            userData = malloc(userDataSize);
            fp = fopen(userDataFileName,"rb");
            if (fp == NULL) {
                pm_message("Could not open userdata file '%s'.",
                           userDataFileName);
                userData = NULL;
                userDataSize = 0;
            } else {
                size_t bytesRead;

                bytesRead = fread(userData,1,userDataSize,fp);
                if (bytesRead != userDataSize) {
                    pm_message("Could not read %d bytes from "
                               "userdata file '%s'.",
                               userDataSize,userDataFileName);
                    userData = NULL;
                    userDataSize = 0;
                }
            }
        } else { /* Put in our UserData Header */
            const char * userDataString;
            time_t now;
                    
            time(&now);
            asprintfN(&userDataString,"MPEG stream encoded by UCB Encoder "
                      "(mpeg_encode) v%s on %s.",
                      VERSION, ctime(&now));
            userData = strdup(userDataString);
            userDataSize = strlen(userData);
            strfree(userDataString);
        }
        Mhead_GenSequenceHeader(bb, Fsize_x, Fsize_y,
                                /* pratio */ aspectRatio,
                                /* pict_rate */ frameRate, 
                                /* bit_rate */ bit_rate,
                                /* buf_size */ buf_size,
                                /*c_param_flag */ 1,
                                /* iq_matrix */ qtable, 
                                /* niq_matrix */ niqtable,
                                /* ext_data */ NULL,
                                /* ext_data_size */ 0,
                                /* user_data */ (uint8*) userData,
                                /* user_data_size */ userDataSize);
    }
}



static void
getPreviousFrame(unsigned int         const frameStart,
                 int                  const referenceFrame,
                 struct inputSource * const inputSourceP,
                 boolean              const childProcess,
                 const char *         const slaveConversion,
                 const char *         const inputConversion,
                 MpegFrame **         const framePP,
                 unsigned int *       const framesReadP,
                 int *                const ioTimeP) {

    MpegFrame * frameP;
    time_t ioTimeStart, ioTimeEnd;

    /* can't find the previous frame interactively */
    if (inputSourceP->stdinUsed)
        pm_error("Cannot encode GOP from stdin when "
                 "first frame is a B-frame.");

    if (frameStart < 1)
        pm_error("Cannot encode GOP when first frame is a B-frame "
                 "and is not preceded by anything.");

    /* need to load in previous frame; call it an I frame */
    frameP = Frame_New(frameStart-1, 'i');

    time(&ioTimeStart);

    if ((referenceFrame == DECODED_FRAME) && childProcess) {
        WaitForDecodedFrame(frameStart);

        if (remoteIO)
            GetRemoteDecodedRefFrame(frameP, frameStart - 1);
        else
            ReadDecodedRefFrame(frameP, frameStart - 1);
    } else
        ReadNthFrame(inputSourceP, frameStart - 1, remoteIO, childProcess,
                     separateConversion, slaveConversion, inputConversion,
                     frameP);
            
    ++(*framesReadP);
    
    time(&ioTimeEnd);
    *ioTimeP += (ioTimeEnd-ioTimeStart);