intrapred.c

Nokia H.264/AVC Encoder/Decoder Usage Manual

/*
COPYRIGHT, LICENSE AND WARRANTY INFORMATION

This software module has been originally developed by Nokia Corporation. 

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(hereinafter Licensee) comply with all the terms and conditions of this 
Statement and subject to the limitations set forth in this Statement Nokia 
grants to such Licensee a non-exclusive, sub-licensable, worldwide, 
limited license under copyrights owned by Nokia to use the Software for 
the sole purpose of creating, manufacturing, selling, marketing, or  
distributing (including the right to make modifications to the Software) 
a fully compliant decoder implementation (hereinafter "Decoder") of 
ITU-T Recommendation H.264 / ISO/IEC International Standard 14496-10 and 
an encoder implementation producing output that is decodable with the 
Decoder.

Nokia retains the ownership of copyrights to the Software. There is no 
patent nor other intellectual property right of Nokia licensed under this 
Statement (except the copyright license above). Licensee hereby assumes 
sole responsibility to secure any other intellectual property rights 
needed, if any. For example, if patent licenses  are required, it is 
their responsibility to acquire the license before utilizing the Software.

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non-exclusive, worldwide, royalty-free, perpetual and irrevocable 
covenant that the Licensee(s) shall not bring a suit before any court or 
administrative agency or otherwise assert a claim for infringement under 
the Licensee intellectual property rights that, but for a license, would 
be infringed by the Software against  
   (a)  Nokia or Nokia's Affiliate; or  
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        to the Software from Nokia; or 
   (c)  contractor, customer or distributor of a party listed above in a 
        or b,  
which suit or claim is related to the Software or use thereof.

The Licensee(s) further agrees to grant a reciprocal license to Nokia 
(as granted by Nokia to the Licensee(s) on the modifications made by 
Licensee(s) to the Software. 

THE SOFTWARE IS PROVIDED "AS IS" AND THE ORIGINAL DEVELOPER DISCLAIMS 
ANY AND ALL WARRANTIES WHETHER EXPRESS, IMPLIED OR STATUTORY, INCLUDING 
BUT NOT LIMITED TO THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS 
FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. THOSE INTENDING TO USE 
THE SOFTWARE ARE EXPRESSLY ADVISED THAT ITS USE MAY INFRINGE EXISTING 
PATENTS AND BE SUBJECT TO ROYALTY PAYMENTS TO PATENT OWNERS. ANYONE 
USING THE SOFTWARE ON THE BASIS OF THIS LICENSE AGREES TO OBTAIN THE 
NECESSARY PERMISSIONS FROM ANY AND ALL APPLICABLE PATENT OWNERS FOR SUCH 
USE.

IN NO EVENT SHALL THE ORIGINAL DEVELOPER BE LIABLE FOR ANY CLAIM, 
DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT 
OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE 
OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

This copyright, license and warranty information notice must be retained 
in all copies and derivative works of the Software or substantial 
portions thereof.
*/



#include "globals.h"
#include "prederrordec.h"
#include "intrapred.h"



/*
 * Prototypes for static functions
 */

static void intraPred4x4(u_int8 predBlk[BLK_SIZE][MBK_SIZE], int mode,
                         u_int8 *reco, int picWidth, int blkAvailBits);


/*
 *
 * intraPred4x4
 *
 * Parameters:
 *      predBlk               Return pointer for predicted pixels
 *      mode                  Prediction for the block
 *      reco                  Reconstruction pixels
 *      picWidth              Horizontal size of the frame
 *      blkAvailBits          Availability of neighboring blocks
 *
 * Function:
 *      Compute prediction for one 4x4 block using given mode
 *
 * Returns:
 *      -
 *
 */
static void intraPred4x4(u_int8 predBlk[BLK_SIZE][MBK_SIZE], int mode,
                         u_int8 *reco, int picWidth, int blkAvailBits)
{
  int i, j;
  int X,A,B,C,D,E,F,G,H,I,J,K,L;
  int dc;


  /*
   * Copy reconstruction pixels used for prediction
   */

  if (blkAvailBits & 0x1000) /* up-left */
    X = reco[0];
  else
    X = 128;

  if (blkAvailBits & 0x0010) { /* up */
    A = reco[1];
    B = reco[2];
    C = reco[3];
    D = reco[4];
    if (blkAvailBits & 0x0100) { /* up-right */
      E = reco[5];
      F = reco[6];
      G = reco[7];
      H = reco[8];
    }
    else
      E = F = G = H = D;
  }
  else
    A = B = C = D = E = F = G = H = 128;

  if (blkAvailBits & 0x0001) { /* left */
    I = reco[1*picWidth];
    J = reco[2*picWidth];
    K = reco[3*picWidth];
    L = reco[4*picWidth];
  }
  else
    I = J = K = L = 128;


  switch (mode) {

  case IPR_MODE_DC:

    /* DC PREDICTION */
    
    if ((blkAvailBits & 0x0010) && (blkAvailBits & 0x0001)) /* up & left */
      dc = (A+B+C+D+I+J+K+L+4)>>3;
    else if (blkAvailBits & 0x0010) /* up */
      dc = (A+B+C+D+2)>>2;
    else if (blkAvailBits & 0x0001) /* left */
      dc = (I+J+K+L+2)>>2;
    else
      dc = 128;
    
    for (j = 0; j < BLK_SIZE; j++) {
      predBlk[j][0] = (u_int8) dc;
      predBlk[j][1] = (u_int8) dc;
      predBlk[j][2] = (u_int8) dc;
      predBlk[j][3] = (u_int8) dc;
    }
      
    break;

  case IPR_MODE_VERT:

    /* VERTICAL PREDICTION */
  
    for (j = 0; j < BLK_SIZE; j++) {
      predBlk[j][0] = (u_int8) A;
      predBlk[j][1] = (u_int8) B;
      predBlk[j][2] = (u_int8) C;
      predBlk[j][3] = (u_int8) D;
    }

    break;

  case IPR_MODE_HOR:

    /* HORIZONTAL PREDICTION */
  
    for (i = 0; i < BLK_SIZE; i++) {
      predBlk[0][i] = (u_int8) I;
      predBlk[1][i] = (u_int8) J;
      predBlk[2][i] = (u_int8) K;
      predBlk[3][i] = (u_int8) L;
    }

    break;

  case IPR_MODE_DIAG_DOWN_RIGHT:

    /* DIAGONAL PREDICTION */
  
    predBlk[3][0] = (u_int8) ((L+2*K+J+2)>>2);
    predBlk[2][0] = 
    predBlk[3][1] = (u_int8) ((K+2*J+I+2)>>2);
    predBlk[1][0] = 
    predBlk[2][1] = 
    predBlk[3][2] = (u_int8) ((J+2*I+X+2)>>2);
    predBlk[0][0] = 
    predBlk[1][1] = 
    predBlk[2][2] = 
    predBlk[3][3] = (u_int8) ((I+2*X+A+2)>>2);
    predBlk[0][1] = 
    predBlk[1][2] = 
    predBlk[2][3] = (u_int8) ((X+2*A+B+2)>>2);
    predBlk[0][2] = 
    predBlk[1][3] = (u_int8) ((A+2*B+C+2)>>2);
    predBlk[0][3] = (u_int8) ((B+2*C+D+2)>>2);

    break;

  case IPR_MODE_DIAG_DOWN_LEFT:
    predBlk[0][0] = (u_int8) ((A+2*B+C+2)>>2);
    predBlk[0][1] = 
    predBlk[1][0] = (u_int8) ((B+2*C+D+2)>>2);
    predBlk[0][2] =
    predBlk[1][1] =
    predBlk[2][0] = (u_int8) ((C+2*D+E+2)>>2);
    predBlk[0][3] = 
    predBlk[1][2] = 
    predBlk[2][1] = 
    predBlk[3][0] = (u_int8) ((D+2*E+F+2)>>2);
    predBlk[1][3] = 
    predBlk[2][2] = 
    predBlk[3][1] = (u_int8) ((E+2*F+G+2)>>2);
    predBlk[2][3] = 
    predBlk[3][2] = (u_int8) ((F+2*G+H+2)>>2);
    predBlk[3][3] = (u_int8) ((G+3*H+2)>>2);

    break;

  case IPR_MODE_VERT_RIGHT:/* diagonal prediction -22.5 deg to horizontal plane */
    predBlk[0][0] = 
    predBlk[2][1] = (u_int8) ((X+A+1)>>1);
    predBlk[0][1] = 
    predBlk[2][2] = (u_int8) ((A+B+1)>>1);
    predBlk[0][2] = 
    predBlk[2][3] = (u_int8) ((B+C+1)>>1);
    predBlk[0][3] = (u_int8) ((C+D+1)>>1);
    predBlk[1][0] = 
    predBlk[3][1] = (u_int8) ((I+2*X+A+2)>>2);
    predBlk[1][1] = 
    predBlk[3][2] = (u_int8) ((X+2*A+B+2)>>2);
    predBlk[1][2] = 
    predBlk[3][3] = (u_int8) ((A+2*B+C+2)>>2);
    predBlk[1][3] = (u_int8) ((B+2*C+D+2)>>2);
    predBlk[2][0] = (u_int8) ((X+2*I+J+2)>>2);
    predBlk[3][0] = (u_int8) ((I+2*J+K+2)>>2);

    break;

  case IPR_MODE_VERT_LEFT:/* diagonal prediction -22.5 deg to horizontal plane */
    predBlk[0][0] = (u_int8) ((A+B+1)>>1);
    predBlk[0][1] = 
    predBlk[2][0] = (u_int8) ((B+C+1)>>1);
    predBlk[0][2] = 
    predBlk[2][1] = (u_int8) ((C+D+1)>>1);
    predBlk[0][3] = 
    predBlk[2][2] = (u_int8) ((D+E+1)>>1);
    predBlk[2][3] = (u_int8) ((E+F+1)>>1);
    predBlk[1][0] = (u_int8) ((A+2*B+C+2)>>2);
    predBlk[1][1] = 
    predBlk[3][0] = (u_int8) ((B+2*C+D+2)>>2);
    predBlk[1][2] = 
    predBlk[3][1] = (u_int8) ((C+2*D+E+2)>>2);
    predBlk[1][3] = 
    predBlk[3][2] = (u_int8) ((D+2*E+F+2)>>2);
    predBlk[3][3] = (u_int8) ((E+2*F+G+2)>>2);

    break;

  case IPR_MODE_HOR_UP:/* diagonal prediction -22.5 deg to horizontal plane */
    predBlk[0][0] = (u_int8) ((I+J+1)>>1);
    predBlk[0][1] = (u_int8) ((I+2*J+K+2)>>2);
    predBlk[0][2] = 
    predBlk[1][0] = (u_int8) ((J+K+1)>>1);
    predBlk[0][3] = 
    predBlk[1][1] = (u_int8) ((J+2*K+L+2)>>2);
    predBlk[1][2] = 
    predBlk[2][0] = (u_int8) ((K+L+1)>>1);
    predBlk[1][3] = 
    predBlk[2][1] = (u_int8) ((K+2*L+L+2)>>2);
    predBlk[2][3] = 
    predBlk[3][1] = 
    predBlk[2][2] = 
    predBlk[3][0] = 
    predBlk[3][2] = 
    predBlk[3][3] = (u_int8) L;

    break;

  case IPR_MODE_HOR_DOWN:/* diagonal prediction -22.5 deg to horizontal plane */
    predBlk[0][0] = 
    predBlk[1][2] = (u_int8) ((X+I+1)>>1);
    predBlk[0][1] = 
    predBlk[1][3] = (u_int8) ((I+2*X+A+2)>>2);
    predBlk[0][2] = (u_int8) ((X+2*A+B+2)>>2);
    predBlk[0][3] = (u_int8) ((A+2*B+C+2)>>2);
    predBlk[1][0] = 
    predBlk[2][2] = (u_int8) ((I+J+1)>>1);
    predBlk[1][1] = 
    predBlk[2][3] = (u_int8) ((X+2*I+J+2)>>2);
    predBlk[2][0] = 
    predBlk[3][2] = (u_int8) ((J+K+1)>>1);
    predBlk[2][1] = 
    predBlk[3][3] = (u_int8) ((I+2*J+K+2)>>2);
    predBlk[3][0] = (u_int8) ((K+L+1)>>1);
    predBlk[3][1] = (u_int8) ((J+2*K+L+2)>>2);
    break;

  default:
    deb0f(stderr, "Illegal 4x4 intra mode\n");
    break;
  }

}


/*
 *
 * iprPredLuma4x4blocks
 *
 * Parameters:
 *      coef                  Transform coefficints for 4x4 blocks
 *      reco                  Reconstruction pixels
 *      picWidth              Horizontal size of the frame
 *      picHeight             Vertical size of the frame
 *      ipModes               Intra prediction modes for the frame
 *      mbAvailBits           Macroblock availability flags
 *      mbIdxX                Horz. location of the MB in the frame
 *      mbIdxY                Vert. location of the MB in the frame
 *      cbp                   Coded Block Pattern
 *      qp                    Quantization parameter
 *
 * Function:
 *      Make 4x4 luma intra prediction for all blocks in the macroblock.
 *
 * Returns:
 *      -
 *
 */
void iprPredLuma4x4blocks(int coef[BLK_PER_MB][BLK_PER_MB][BLK_SIZE][BLK_SIZE],
                          u_int8 *reco, int picWidth, int8 *ipModes,
                          int mbAvailBits, int mbIdxX, int mbIdxY, int cbp, int qp)
{
  u_int8 predY[BLK_SIZE][MBK_SIZE];
  int blkIdxX, blkIdxY;
  int blkAvailUp, blkAvailLeft, blkAvailUpRight, blkAvailUpLeft;
  u_int8 *recoPtr;
  int blkAvailBits;
  int blkNum;

  recoPtr = &reco[mbIdxY*MBK_SIZE*picWidth+mbIdxX*MBK_SIZE];

  /*
   * Check block availability (1 bit per block, 4 directions)
   */

  blkAvailUp = (mbAvailBits & 2) ? 0xFFFF : 0xFFF0;

  blkAvailLeft = (mbAvailBits & 1) ? 0xFFFF : 0xEEEE;

  blkAvailUpRight = 0x5750;
  if (mbAvailBits & 2) blkAvailUpRight |= 0x0007;
  if (mbAvailBits & 4) blkAvailUpRight |= 0x0008;

  blkAvailUpLeft = 0xEEE0;
  if (mbAvailBits & 2) blkAvailUpLeft |= 0x000E;
  if (mbAvailBits & 1) blkAvailUpLeft |= 0x1110;
  if (mbAvailBits & 8) blkAvailUpLeft |= 0x0001;

  /*
   * Build 4x4 intra prediction
   */

  for (blkIdxY = 0; blkIdxY < BLK_PER_MB; blkIdxY++) {

    /* Gather availability bits for 4 blocks in raster scan order */
    blkAvailBits = ( blkAvailLeft    & 0x000f       ) |
                   ((blkAvailUp      & 0x000f) <<  4) |
                   ((blkAvailUpRight & 0x000f) <<  8) |
                   ((blkAvailUpLeft  & 0x000f) << 12);

    /* Next 4 blocks */
    blkAvailLeft    >>= 4;
    blkAvailUp      >>= 4;
    blkAvailUpRight >>= 4;
    blkAvailUpLeft  >>= 4;

    for (blkIdxX = 0; blkIdxX < BLK_PER_MB; blkIdxX++) {

      blkNum = blkIdxY*BLK_PER_MB+blkIdxX;

      /* Make all possible 4x4 predictions for current block */
      intraPred4x4(predY, ipModes[blkIdxX],
                   &recoPtr[blkIdxX*BLK_SIZE-picWidth-1],
                   picWidth, blkAvailBits);

      if ((cbp>>blkNum) & 1) {
        pedRecoBlock(predY, coef[blkIdxY][blkIdxX],
                     &recoPtr[blkIdxX*BLK_SIZE], picWidth, 0, 0, qp);
      }
      else {
        pedRecoBlockNoCoef(predY, &recoPtr[blkIdxX*BLK_SIZE], picWidth);
      }

      blkAvailBits >>= 1;
    }

    recoPtr   += BLK_SIZE*picWidth;
    ipModes += BLK_PER_MB;
  }

}


/*
 *
 * iprPredLuma16x16