/src/libmpeg2/common/ideint_cac.c

Source
/******************************************************************************
 *
 * 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
*  ideint_cac.c
*
* @brief
*  This file include the definitions of the combing  artifact check function
* of the de-interlacer and some  variant of that.
*
* @author
*  Ittiam
*
* @par List of Functions:
*  cac_4x8()
*  ideint_cac()
*
* @remarks
*  In the de-interlacer workspace, cac is not a seperate  assembly module as
* it comes along with the  de_int_decision() function. But in C-Model, to
* keep  the things cleaner, it was made to be a separate  function during
* cac experiments long after the  assembly was written by Mudit.
*
*******************************************************************************
*/
/*****************************************************************************/
/* File Includes                                                             */
/*****************************************************************************/
/* System include files */
#include <stdio.h>
#include <stdint.h>
#include <string.h>
#include <stdlib.h>

/* User include files */
#include "icv_datatypes.h"
#include "icv_macros.h"
#include "icv.h"
#include "icv_variance.h"
#include "icv_sad.h"
#include "ideint.h"
#include "ideint_defs.h"
#include "ideint_structs.h"
#include "ideint_cac.h"

/**
*******************************************************************************
*
* @brief
* Combing artifact check function for 8x4 block
*
* @par   Description
*  Adjacent and alternate SADs are calculated by row based and column-based
*  collapsing. The adjacent and alternate SADs are then compared with some
*  biasing to get CAC
*
* @param[in] pu1_top
*  Top field
*
* @param[in] pu1_bot
*  Bottom field
*
* @param[in] top_strd
*  Top field Stride
*
* @param[in] bot_strd
*  Bottom field stride
*
* @param[in] pi4_adj_sad
*  Pointer to return adjacent SAD
*
* @param[in] pi4_alt_sad
*  Pointer to return alternate SAD
*
* @returns
* combing artifact flag (1 = detected, 0 = not detected)
*
* @remarks
*
*******************************************************************************
*/
static WORD32 cac_4x8(UWORD8 *pu1_top,
                      UWORD8 *pu1_bot,
                      WORD32 top_strd,
                      WORD32 bot_strd)
{
    WORD32 ca;
    WORD32 adj;
    WORD32 alt;
    UWORD8 *pu1_tmp_top;
    UWORD8 *pu1_tmp_bot;
    WORD32 i;
    WORD32 j;
    UWORD8 *pu1_top_0;
    UWORD8 *pu1_top_1;
    UWORD8 *pu1_top_2;
    UWORD8 *pu1_top_3;
    UWORD8 *pu1_bot_0;
    UWORD8 *pu1_bot_1;
    UWORD8 *pu1_bot_2;
    UWORD8 *pu1_bot_3;
    WORD32 rsum_csum_thresh;
    WORD32 sad_bias_mult_shift;
    WORD32 sad_bias_additive;

    WORD32 diff_sum;
    WORD32 top_row_end_incr;
    WORD32 bot_row_end_incr;

    ca = 0;

    adj = 0;
    alt = 0;

    rsum_csum_thresh    = RSUM_CSUM_THRESH;
    sad_bias_additive   = SAD_BIAS_ADDITIVE;
    sad_bias_mult_shift = SAD_BIAS_MULT_SHIFT;

    /*************************************************************************/
    /* In the adjacent sad calculation by row-method, the absolute           */
    /* difference is taken between the adjacent rows. The pixels of the diff */
    /* row, thus obtained, are then summed up. If this sum of absolute       */
    /* differace (sad) is greater than a threshold value, it is added to the */
    /* adjcacent SAD value.                                                  */
    /*************************************************************************/

    /*************************************************************************/
    /* Adj dif: Row based                                                    */
    /*************************************************************************/

    pu1_tmp_top = pu1_top;
    pu1_tmp_bot = pu1_bot;

    top_row_end_incr = top_strd - SUB_BLK_WD;
    bot_row_end_incr = bot_strd - SUB_BLK_WD;

    /*************************************************************************/
    /* The outer-loop runs for BLK_HT/2 times, because one pixel   */
    /* is touched only once.                                                 */
    /*************************************************************************/
    for(j = 0; j < BLK_HT; j += 4)
    {
        WORD32 sum_1, sum_2, sum_3, sum_4;
        WORD32 sum_diff;

        /*********************************************************************/
        /* Because the 8x4 is split into two halves of 4x4, the width of the */
        /* block is now 4.                                                   */
        /*********************************************************************/
        sum_1 = 0;
        sum_2 = 0;

        for(i = 0; i < SUB_BLK_WD; i ++)
        {
            sum_1 += *pu1_tmp_top++;
            sum_2 += *pu1_tmp_bot++;
        }

        sum_diff = ABS_DIF(sum_1, sum_2);

        /*********************************************************************/
        /* Thresholding.                                                     */
        /*********************************************************************/
        if(sum_diff >= rsum_csum_thresh)
            adj += sum_diff;

        pu1_tmp_top += top_row_end_incr;
        pu1_tmp_bot += bot_row_end_incr;


        sum_3 = 0;
        sum_4 = 0;

        for(i = 0; i < SUB_BLK_WD; i ++)
        {
            sum_3 += *pu1_tmp_top++;
            sum_4 += *pu1_tmp_bot++;
        }

        sum_diff = ABS_DIF(sum_3, sum_4);

        /*********************************************************************/
        /* Thresholding.                                                     */
        /*********************************************************************/
        if(sum_diff >= rsum_csum_thresh)
            adj += sum_diff;

        pu1_tmp_top += top_row_end_incr;
        pu1_tmp_bot += bot_row_end_incr;

        /*************************************************************************/
        /* Alt diff : Row based                                                  */
        /*************************************************************************/
        alt += ABS_DIF(sum_1, sum_3);
        alt += ABS_DIF(sum_2, sum_4);

    }

    /*************************************************************************/
    /* In the adjacent sad calculation by column-method, the rows of both    */
    /* the fields are averaged separately and then summed across the column. */
    /* The difference of the two values, thus obtained, is added to the      */
    /* adjacent sad value, if it is beyond the threshold.                    */
    /*************************************************************************/

    pu1_top_0 = pu1_top;
    pu1_top_1 = pu1_top_0 + top_strd;
    pu1_top_2 = pu1_top_1 + top_strd;
    pu1_top_3 = pu1_top_2 + top_strd;

    pu1_bot_0 = pu1_bot;
    pu1_bot_1 = pu1_bot_0 + bot_strd;
    pu1_bot_2 = pu1_bot_1 + bot_strd;
    pu1_bot_3 = pu1_bot_2 + bot_strd;

    /*************************************************************************/
    /* Adj dif: Col based                                                    */
    /*************************************************************************/
    diff_sum = 0;

    /*************************************************************************/
    /* As the DSP implementation of this modules is anyway going to assume   */
    /* the size of the block to the fixed (8x4 or two 4x4's), the height of  */
    /* block is also kept to be 8, to have a clean implementation.           */
    /*************************************************************************/
    for(i = 0; i < SUB_BLK_WD; i ++)
    {
        WORD32 val_1;
        WORD32 val_2;
        WORD32 tmp_1, tmp_2;
        WORD32 tmp_diff;

        tmp_1 = AVG(pu1_top_0[i], pu1_top_1[i]);
        tmp_2 = AVG(pu1_top_2[i], pu1_top_3[i]);
        val_1 = AVG(tmp_1,        tmp_2);

        tmp_1 = AVG(pu1_bot_0[i], pu1_bot_1[i]);
        tmp_2 = AVG(pu1_bot_2[i], pu1_bot_3[i]);
        val_2 = AVG(tmp_1,        tmp_2);

        tmp_diff = ABS_DIF(val_1, val_2);

        if(tmp_diff >= (rsum_csum_thresh >> 2))
            diff_sum += tmp_diff;
    }


    adj += diff_sum << 2;

    /*************************************************************************/
    /* Alt diff : Col based                                                  */
    /*************************************************************************/
    diff_sum = 0;

    for(i = 0; i < SUB_BLK_WD; i ++)
    {
        WORD32 val_1;
        WORD32 val_2;
        WORD32 tmp_1, tmp_2;
        WORD32 tmp_diff;

        tmp_1 = AVG(pu1_top_0[i], pu1_bot_0[i]);
        tmp_2 = AVG(pu1_top_2[i], pu1_bot_2[i]);
        val_1 = AVG(tmp_1,        tmp_2);

        tmp_1 = AVG(pu1_top_1[i], pu1_bot_1[i]);
        tmp_2 = AVG(pu1_top_3[i], pu1_bot_3[i]);
        val_2 = AVG(tmp_1, tmp_2);

        tmp_diff = ABS_DIF(val_1, val_2);

        diff_sum += tmp_diff;
    }

    /*************************************************************************/
    /* because of the averaging used in place of summation, a factor of 4 is */
    /* needed while adding the the diff_sum to the sad.                      */
    /*************************************************************************/

    alt += diff_sum << 2;

    pu1_top += SUB_BLK_WD;
    pu1_bot += SUB_BLK_WD;

    alt += (alt >> sad_bias_mult_shift) + (sad_bias_additive >> 1);
    ca   = (alt < adj);

    return ca;
}

/**
*******************************************************************************
*
* @brief
* Combing artifact check function for 8x8 block
*
* @par   Description
* Determines CAC for 8x8 block by calling 8x4 CAC function
*
* @param[in] pu1_top
*  Top field
*
* @param[in] pu1_bot
*  Bottom field
*
* @param[in] top_strd
*  Top field Stride
*
* @param[in] bot_strd
*  Bottom field stride
*
* @returns
* combing artifact flag (1 = detected, 0 = not detected)
*
* @remarks
*
*******************************************************************************
*/
WORD32 ideint_cac_8x8(UWORD8 *pu1_top,
                      UWORD8 *pu1_bot,
                      WORD32 top_strd,
                      WORD32 bot_strd)
{
    WORD32 ca;        /* combing artifact result                          */
    WORD32 k;

    ca = 0;
    /*************************************************************************/
    /* This loop runs for the two halves of the 4x8 block.                   */
    /*************************************************************************/
    for(k = 0; k < 2; k ++)
    {
        ca |= cac_4x8(pu1_top, pu1_bot, top_strd, bot_strd);

        pu1_top += SUB_BLK_WD;
        pu1_bot += SUB_BLK_WD;

        /* If Combing Artifact is detected, then return. Else continue to
         * check the next half
         */
        if(ca)
            return ca;
    }

    return ca;
}


Coverage Report

Created: 2025-08-11 06:35

Line	Count	Source
1		/******************************************************************************
2		*
3		* Copyright (C) 2015 The Android Open Source Project
4		*
5		* Licensed under the Apache License, Version 2.0 (the "License");
6		* you may not use this file except in compliance with the License.
7		* You may obtain a copy of the License at:
8		*
9		* http://www.apache.org/licenses/LICENSE-2.0
10		*
11		* Unless required by applicable law or agreed to in writing, software
12		* distributed under the License is distributed on an "AS IS" BASIS,
13		* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14		* See the License for the specific language governing permissions and
15		* limitations under the License.
16		*
17		*****************************************************************************
18		* Originally developed and contributed by Ittiam Systems Pvt. Ltd, Bangalore
19		*/
20		/**
21		*******************************************************************************
22		* @file
23		* ideint_cac.c
24		*
25		* @brief
26		* This file include the definitions of the combing artifact check function
27		* of the de-interlacer and some variant of that.
28		*
29		* @author
30		* Ittiam
31		*
32		* @par List of Functions:
33		* cac_4x8()
34		* ideint_cac()
35		*
36		* @remarks
37		* In the de-interlacer workspace, cac is not a seperate assembly module as
38		* it comes along with the de_int_decision() function. But in C-Model, to
39		* keep the things cleaner, it was made to be a separate function during
40		* cac experiments long after the assembly was written by Mudit.
41		*
42		*******************************************************************************
43		*/
44		/*****************************************************************************/
45		/* File Includes */
46		/*****************************************************************************/
47		/* System include files */
48		#include <stdio.h>
49		#include <stdint.h>
50		#include <string.h>
51		#include <stdlib.h>
52
53		/* User include files */
54		#include "icv_datatypes.h"
55		#include "icv_macros.h"
56		#include "icv.h"
57		#include "icv_variance.h"
58		#include "icv_sad.h"
59		#include "ideint.h"
60		#include "ideint_defs.h"
61		#include "ideint_structs.h"
62		#include "ideint_cac.h"
63
64		/**
65		*******************************************************************************
66		*
67		* @brief
68		* Combing artifact check function for 8x4 block
69		*
70		* @par Description
71		* Adjacent and alternate SADs are calculated by row based and column-based
72		* collapsing. The adjacent and alternate SADs are then compared with some
73		* biasing to get CAC
74		*
75		* @param[in] pu1_top
76		* Top field
77		*
78		* @param[in] pu1_bot
79		* Bottom field
80		*
81		* @param[in] top_strd
82		* Top field Stride
83		*
84		* @param[in] bot_strd
85		* Bottom field stride
86		*
87		* @param[in] pi4_adj_sad
88		* Pointer to return adjacent SAD
89		*
90		* @param[in] pi4_alt_sad
91		* Pointer to return alternate SAD
92		*
93		* @returns
94		* combing artifact flag (1 = detected, 0 = not detected)
95		*
96		* @remarks
97		*
98		*******************************************************************************
99		*/
100		static WORD32 cac_4x8(UWORD8 *pu1_top,
101		UWORD8 *pu1_bot,
102		WORD32 top_strd,
103		WORD32 bot_strd)
104	7.24M	{
105	7.24M	WORD32 ca;
106	7.24M	WORD32 adj;
107	7.24M	WORD32 alt;
108	7.24M	UWORD8 *pu1_tmp_top;
109	7.24M	UWORD8 *pu1_tmp_bot;
110	7.24M	WORD32 i;
111	7.24M	WORD32 j;
112	7.24M	UWORD8 *pu1_top_0;
113	7.24M	UWORD8 *pu1_top_1;
114	7.24M	UWORD8 *pu1_top_2;
115	7.24M	UWORD8 *pu1_top_3;
116	7.24M	UWORD8 *pu1_bot_0;
117	7.24M	UWORD8 *pu1_bot_1;
118	7.24M	UWORD8 *pu1_bot_2;
119	7.24M	UWORD8 *pu1_bot_3;
120	7.24M	WORD32 rsum_csum_thresh;
121	7.24M	WORD32 sad_bias_mult_shift;
122	7.24M	WORD32 sad_bias_additive;
123
124	7.24M	WORD32 diff_sum;
125	7.24M	WORD32 top_row_end_incr;
126	7.24M	WORD32 bot_row_end_incr;
127
128	7.24M	ca = 0;
129
130	7.24M	adj = 0;
131	7.24M	alt = 0;
132
133	7.24M	rsum_csum_thresh = RSUM_CSUM_THRESH;
134	7.24M	sad_bias_additive = SAD_BIAS_ADDITIVE;
135	7.24M	sad_bias_mult_shift = SAD_BIAS_MULT_SHIFT;
136
137		/*************************************************************************/
138		/* In the adjacent sad calculation by row-method, the absolute */
139		/* difference is taken between the adjacent rows. The pixels of the diff */
140		/* row, thus obtained, are then summed up. If this sum of absolute */
141		/* differace (sad) is greater than a threshold value, it is added to the */
142		/* adjcacent SAD value. */
143		/*************************************************************************/
144
145		/*************************************************************************/
146		/* Adj dif: Row based */
147		/*************************************************************************/
148
149	7.24M	pu1_tmp_top = pu1_top;
150	7.24M	pu1_tmp_bot = pu1_bot;
151
152	7.24M	top_row_end_incr = top_strd - SUB_BLK_WD;
153	7.24M	bot_row_end_incr = bot_strd - SUB_BLK_WD;
154
155		/*************************************************************************/
156		/* The outer-loop runs for BLK_HT/2 times, because one pixel */
157		/* is touched only once. */
158		/*************************************************************************/
159	21.3M	for(j = 0; j < BLK_HT; j += 4)
160	14.1M	{
161	14.1M	WORD32 sum_1, sum_2, sum_3, sum_4;
162	14.1M	WORD32 sum_diff;
163
164		/*********************************************************************/
165		/* Because the 8x4 is split into two halves of 4x4, the width of the */
166		/* block is now 4. */
167		/*********************************************************************/
168	14.1M	sum_1 = 0;
169	14.1M	sum_2 = 0;
170
171	70.7M	for(i = 0; i < SUB_BLK_WD; i ++)
172	56.5M	{
173	56.5M	sum_1 += *pu1_tmp_top++;
174	56.5M	sum_2 += *pu1_tmp_bot++;
175	56.5M	}
176
177	14.1M	sum_diff = ABS_DIF(sum_1, sum_2);
178
179		/*********************************************************************/
180		/* Thresholding. */
181		/*********************************************************************/
182	14.1M	if(sum_diff >= rsum_csum_thresh)
183	167k	adj += sum_diff;
184
185	14.1M	pu1_tmp_top += top_row_end_incr;
186	14.1M	pu1_tmp_bot += bot_row_end_incr;
187
188
189	14.1M	sum_3 = 0;
190	14.1M	sum_4 = 0;
191
192	70.6M	for(i = 0; i < SUB_BLK_WD; i ++)
193	56.4M	{
194	56.4M	sum_3 += *pu1_tmp_top++;
195	56.4M	sum_4 += *pu1_tmp_bot++;
196	56.4M	}
197
198	14.1M	sum_diff = ABS_DIF(sum_3, sum_4);
199
200		/*********************************************************************/
201		/* Thresholding. */
202		/*********************************************************************/
203	14.1M	if(sum_diff >= rsum_csum_thresh)
204	166k	adj += sum_diff;
205
206	14.1M	pu1_tmp_top += top_row_end_incr;
207	14.1M	pu1_tmp_bot += bot_row_end_incr;
208
209		/*************************************************************************/
210		/* Alt diff : Row based */
211		/*************************************************************************/
212	14.1M	alt += ABS_DIF(sum_1, sum_3);
213	14.1M	alt += ABS_DIF(sum_2, sum_4);
214
215	14.1M	}
216
217		/*************************************************************************/
218		/* In the adjacent sad calculation by column-method, the rows of both */
219		/* the fields are averaged separately and then summed across the column. */
220		/* The difference of the two values, thus obtained, is added to the */
221		/* adjacent sad value, if it is beyond the threshold. */
222		/*************************************************************************/
223
224	7.24M	pu1_top_0 = pu1_top;
225	7.24M	pu1_top_1 = pu1_top_0 + top_strd;
226	7.24M	pu1_top_2 = pu1_top_1 + top_strd;
227	7.24M	pu1_top_3 = pu1_top_2 + top_strd;
228
229	7.24M	pu1_bot_0 = pu1_bot;
230	7.24M	pu1_bot_1 = pu1_bot_0 + bot_strd;
231	7.24M	pu1_bot_2 = pu1_bot_1 + bot_strd;
232	7.24M	pu1_bot_3 = pu1_bot_2 + bot_strd;
233
234		/*************************************************************************/
235		/* Adj dif: Col based */
236		/*************************************************************************/
237	7.24M	diff_sum = 0;
238
239		/*************************************************************************/
240		/* As the DSP implementation of this modules is anyway going to assume */
241		/* the size of the block to the fixed (8x4 or two 4x4's), the height of */
242		/* block is also kept to be 8, to have a clean implementation. */
243		/*************************************************************************/
244	35.2M	for(i = 0; i < SUB_BLK_WD; i ++)
245	28.0M	{
246	28.0M	WORD32 val_1;
247	28.0M	WORD32 val_2;
248	28.0M	WORD32 tmp_1, tmp_2;
249	28.0M	WORD32 tmp_diff;
250
251	28.0M	tmp_1 = AVG(pu1_top_0[i], pu1_top_1[i]);
252	28.0M	tmp_2 = AVG(pu1_top_2[i], pu1_top_3[i]);
253	28.0M	val_1 = AVG(tmp_1, tmp_2);
254
255	28.0M	tmp_1 = AVG(pu1_bot_0[i], pu1_bot_1[i]);
256	28.0M	tmp_2 = AVG(pu1_bot_2[i], pu1_bot_3[i]);
257	28.0M	val_2 = AVG(tmp_1, tmp_2);
258
259	28.0M	tmp_diff = ABS_DIF(val_1, val_2);
260
261	28.0M	if(tmp_diff >= (rsum_csum_thresh >> 2))
262	463k	diff_sum += tmp_diff;
263	28.0M	}
264
265
266	7.24M	adj += diff_sum << 2;
267
268		/*************************************************************************/
269		/* Alt diff : Col based */
270		/*************************************************************************/
271	7.24M	diff_sum = 0;
272
273	34.9M	for(i = 0; i < SUB_BLK_WD; i ++)
274	27.7M	{
275	27.7M	WORD32 val_1;
276	27.7M	WORD32 val_2;
277	27.7M	WORD32 tmp_1, tmp_2;
278	27.7M	WORD32 tmp_diff;
279
280	27.7M	tmp_1 = AVG(pu1_top_0[i], pu1_bot_0[i]);
281	27.7M	tmp_2 = AVG(pu1_top_2[i], pu1_bot_2[i]);
282	27.7M	val_1 = AVG(tmp_1, tmp_2);
283
284	27.7M	tmp_1 = AVG(pu1_top_1[i], pu1_bot_1[i]);
285	27.7M	tmp_2 = AVG(pu1_top_3[i], pu1_bot_3[i]);
286	27.7M	val_2 = AVG(tmp_1, tmp_2);
287
288	27.7M	tmp_diff = ABS_DIF(val_1, val_2);
289
290	27.7M	diff_sum += tmp_diff;
291	27.7M	}
292
293		/*************************************************************************/
294		/* because of the averaging used in place of summation, a factor of 4 is */
295		/* needed while adding the the diff_sum to the sad. */
296		/*************************************************************************/
297
298	7.24M	alt += diff_sum << 2;
299
300	7.24M	pu1_top += SUB_BLK_WD;
301	7.24M	pu1_bot += SUB_BLK_WD;
302
303	7.24M	alt += (alt >> sad_bias_mult_shift) + (sad_bias_additive >> 1);
304	7.24M	ca = (alt < adj);
305
306	7.24M	return ca;
307	7.24M	}
308
309		/**
310		*******************************************************************************
311		*
312		* @brief
313		* Combing artifact check function for 8x8 block
314		*
315		* @par Description
316		* Determines CAC for 8x8 block by calling 8x4 CAC function
317		*
318		* @param[in] pu1_top
319		* Top field
320		*
321		* @param[in] pu1_bot
322		* Bottom field
323		*
324		* @param[in] top_strd
325		* Top field Stride
326		*
327		* @param[in] bot_strd
328		* Bottom field stride
329		*
330		* @returns
331		* combing artifact flag (1 = detected, 0 = not detected)
332		*
333		* @remarks
334		*
335		*******************************************************************************
336		*/
337		WORD32 ideint_cac_8x8(UWORD8 *pu1_top,
338		UWORD8 *pu1_bot,
339		WORD32 top_strd,
340		WORD32 bot_strd)
341	4.32M	{
342	4.32M	WORD32 ca; /* combing artifact result */
343	4.32M	WORD32 k;
344
345	4.32M	ca = 0;
346		/*************************************************************************/
347		/* This loop runs for the two halves of the 4x8 block. */
348		/*************************************************************************/
349	11.4M	for(k = 0; k < 2; k ++)
350	7.15M	{
351	7.15M	ca \|= cac_4x8(pu1_top, pu1_bot, top_strd, bot_strd);
352
353	7.15M	pu1_top += SUB_BLK_WD;
354	7.15M	pu1_bot += SUB_BLK_WD;
355
356		/* If Combing Artifact is detected, then return. Else continue to
357		* check the next half
358		*/
359	7.15M	if(ca)
360	37.6k	return ca;
361	7.15M	}
362
363	4.29M	return ca;
364	4.32M	}
365