/******************************************************************************
 *
 * Copyright (C) 2015 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at:
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 *****************************************************************************
 * Originally developed and contributed by Ittiam Systems Pvt. Ltd, Bangalore
*/

/**
 *******************************************************************************
 * @file
 *  ih264e_me.h
 *
 * @brief
 *  Contains declarations of global variables for H264 encoder
 *
 * @author
 *  ittiam
 *
 * @remarks
 *
 *******************************************************************************
 */

#ifndef IH264E_ME_H_
#define IH264E_ME_H_

/*****************************************************************************/
/* Function Macros                                                           */
/*****************************************************************************/

/**
******************************************************************************
 *  @brief      compute median of 3 elements (a, b, c) and store the output
 *  in to result. This is used for mv prediction
******************************************************************************
 */

#define MEDIAN(a, b, c, result) if (a > b){\
                                    if (b > c)\
                                        result = b;\
                                    else {\
                                        if (a > c)\
                                            result = c;\
                                        else \
                                            result = a;\
                                    }\
                                }\
                                else {\
                                    if (c > b)\
                                        result = b;\
                                    else {\
                                        if (c > a)\
                                            result = c;\
                                        else \
                                            result = a;\
                                    }\
                                }


/*****************************************************************************/
/* Extern Function Declarations                                              */
/*****************************************************************************/

/**
*******************************************************************************
*
* @brief
*  This function populates the length of the codewords for motion vectors in the
*  range (-search range, search range) in pixels
*
* @param[in] ps_me
*  Pointer to me ctxt
*
* @param[out] pu1_mv_bits
*  length of the codeword for all mv's
*
* @remarks The length of the code words are derived from signed exponential
* goloumb codes.
*
*******************************************************************************
*/
void ih264e_init_mv_bits
    (
        me_ctxt_t *ps_me
    );

/**
*******************************************************************************
*
* @brief The function gives the skip motion vector
*
* @par Description:
*  The function gives the skip motion vector
*
* @param[in] ps_left_mb_pu
*  pointer to left mb motion vector info
*
* @param[in] ps_top_row_pu
*  pointer to top & top right mb motion vector info
*
* @param[out] ps_pred_mv
*  pointer to candidate predictors for the current block
*
* @returns The x & y components of the MV predictor.
*
* @remarks The code implements the logic as described in sec 8.4.1.1 in H264
*   specification.
*
*******************************************************************************
*/
void ih264e_find_skip_motion_vector
    (
        process_ctxt_t *ps_proc,
        UWORD32 u4_for_me
    );

/**
*******************************************************************************
*
* @brief motion vector predictor
*
* @par Description:
*  The routine calculates the motion vector predictor for a given block,
*  given the candidate MV predictors.
*
* @param[in] ps_left_mb_pu
*  pointer to left mb motion vector info
*
* @param[in] ps_top_row_pu
*  pointer to top & top right mb motion vector info
*
* @param[out] ps_pred_mv
*  pointer to candidate predictors for the current block
*
* @returns  The x & y components of the MV predictor.
*
* @remarks The code implements the logic as described in sec 8.4.1.3 in H264
*   specification.
*   Assumptions : 1. Assumes Single reference frame
*                 2. Assumes Only partition of size 16x16
*
*******************************************************************************
*/
void ih264e_get_mv_predictor
        (
            enc_pu_t *ps_left_mb_pu,
            enc_pu_t *ps_top_row_pu,
            mv_t *ps_pred_mv
        );

/**
*******************************************************************************
*
* @brief This function computes the best motion vector for the current mb
*
* @par Description:
*  This function currently does nothing except set motion vectors from external
*  source
*
* @param[in] ps_proc
*  Process context corresponding to the job
*
* @returns  none
*
* @remarks none
*
*******************************************************************************
*/
void ih264e_compute_me
    (
        process_ctxt_t *ps_proc
    );

/**
*******************************************************************************
*
* @brief This function initializes me ctxt
*
* @par Description:
*  Before dispatching the current job to me thread, the me context associated
*  with the job is initialized.
*
* @param[in] ps_proc
*  Process context corresponding to the job
*
* @returns  none
*
* @remarks none
*
*******************************************************************************
*/
void ih264e_init_me(process_ctxt_t *ps_proc);

/**
*******************************************************************************
*
* @brief This function performs motion estimation for the current NMB
*
* @par Description:
*  Intializes input and output pointers required by the function ih264e_compute_me
*  and calls the function ih264e_compute_me in a loop to process NMBs.
*
* @param[in] ps_proc
*  Process context corresponding to the job
*
* @returns
*
* @remarks none
*
*******************************************************************************
*/
void ih264e_compute_me_nmb
    (
        process_ctxt_t *ps_proc,
        UWORD32 u4_nmb_count
    );

/**
*******************************************************************************
*
* @brief This function performs MV prediction
*
* @par Description:
*
* @param[in] ps_proc
*  Process context corresponding to the job
*
* @returns  none
*
* @remarks none
*  This function will update the MB availability since intra inter decision
*  should be done before the call
*
*******************************************************************************
*/
void ih264e_mv_pred
    (
        process_ctxt_t *ps_proc
    );

/**
*******************************************************************************
*
* @brief This function approximates Pred. MV
*
* @par Description:
*
* @param[in] ps_proc
*  Process context corresponding to the job
*
* @returns  none
*
* @remarks none
*  Motion estimation happens at nmb level. For cost calculations, mv is appro
*  ximated using this function
*
*******************************************************************************
*/
void ih264e_mv_pred_me
    (
        process_ctxt_t *ps_proc
    );

#endif /* IH264E_ME_H_ */