ac3enc: merge compute_exp_strategy_ch() into compute_exp_strategy()
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@ -560,56 +560,47 @@ static void extract_exponents(AC3EncodeContext *s)
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#define EXP_DIFF_THRESHOLD 500
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/**
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* Calculate exponent strategies for all blocks in a single channel.
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*/
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static void compute_exp_strategy_ch(AC3EncodeContext *s, uint8_t *exp_strategy,
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uint8_t *exp)
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{
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int blk, blk1;
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int exp_diff;
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/* estimate if the exponent variation & decide if they should be
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reused in the next frame */
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exp_strategy[0] = EXP_NEW;
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exp += AC3_MAX_COEFS;
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for (blk = 1; blk < AC3_MAX_BLOCKS; blk++) {
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exp_diff = s->dsp.sad[0](NULL, exp, exp - AC3_MAX_COEFS, 16, 16);
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if (exp_diff > EXP_DIFF_THRESHOLD)
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exp_strategy[blk] = EXP_NEW;
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else
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exp_strategy[blk] = EXP_REUSE;
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exp += AC3_MAX_COEFS;
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}
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/* now select the encoding strategy type : if exponents are often
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recoded, we use a coarse encoding */
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blk = 0;
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while (blk < AC3_MAX_BLOCKS) {
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blk1 = blk + 1;
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while (blk1 < AC3_MAX_BLOCKS && exp_strategy[blk1] == EXP_REUSE)
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blk1++;
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switch (blk1 - blk) {
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case 1: exp_strategy[blk] = EXP_D45; break;
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case 2:
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case 3: exp_strategy[blk] = EXP_D25; break;
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default: exp_strategy[blk] = EXP_D15; break;
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}
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blk = blk1;
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}
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}
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/**
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* Calculate exponent strategies for all channels.
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* Array arrangement is reversed to simplify the per-channel calculation.
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*/
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static void compute_exp_strategy(AC3EncodeContext *s)
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{
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int ch, blk;
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int ch, blk, blk1;
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for (ch = 0; ch < s->fbw_channels; ch++) {
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compute_exp_strategy_ch(s, s->exp_strategy[ch], s->blocks[0].exp[ch]);
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uint8_t *exp_strategy = s->exp_strategy[ch];
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uint8_t *exp = s->blocks[0].exp[ch];
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int exp_diff;
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/* estimate if the exponent variation & decide if they should be
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reused in the next frame */
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exp_strategy[0] = EXP_NEW;
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exp += AC3_MAX_COEFS;
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for (blk = 1; blk < AC3_MAX_BLOCKS; blk++) {
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exp_diff = s->dsp.sad[0](NULL, exp, exp - AC3_MAX_COEFS, 16, 16);
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if (exp_diff > EXP_DIFF_THRESHOLD)
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exp_strategy[blk] = EXP_NEW;
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else
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exp_strategy[blk] = EXP_REUSE;
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exp += AC3_MAX_COEFS;
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}
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/* now select the encoding strategy type : if exponents are often
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recoded, we use a coarse encoding */
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blk = 0;
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while (blk < AC3_MAX_BLOCKS) {
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blk1 = blk + 1;
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while (blk1 < AC3_MAX_BLOCKS && exp_strategy[blk1] == EXP_REUSE)
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blk1++;
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switch (blk1 - blk) {
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case 1: exp_strategy[blk] = EXP_D45; break;
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case 2:
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case 3: exp_strategy[blk] = EXP_D25; break;
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default: exp_strategy[blk] = EXP_D15; break;
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}
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blk = blk1;
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}
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}
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if (s->lfe_on) {
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ch = s->lfe_channel;
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