Function ff_tx_init_subtx

libavutil/tx.c:712–901

}

av_cold int ff_tx_init_subtx(AVTXContext *s, enum AVTXType type,
                             uint64_t flags, FFTXCodeletOptions *opts,
                             int len, int inv, const void *scale)
{
    int ret = 0;
    AVTXContext *sub = NULL;
    TXCodeletMatch *cd_tmp, *cd_matches = NULL;
    unsigned int cd_matches_size = 0;
    int codelet_list_idx = codelet_list_num;
    int nb_cd_matches = 0;
#if !CONFIG_SMALL
    AVBPrint bp;
#endif

    /* We still accept functions marked with SLOW, even if the CPU is
     * marked with the same flag, but we give them lower priority. */
    const int cpu_flags = av_get_cpu_flags();

    /* Flags the transform wants */
    uint64_t req_flags = flags;

    /* Flags the codelet may require to be present */
    uint64_t inv_req_mask = AV_TX_FULL_IMDCT |
                            AV_TX_REAL_TO_REAL |
                            AV_TX_REAL_TO_IMAGINARY |
                            FF_TX_PRESHUFFLE |
                            FF_TX_ASM_CALL;

    /* Unaligned codelets are compatible with the aligned flag */
    if (req_flags & FF_TX_ALIGNED)
        req_flags |= AV_TX_UNALIGNED;

    /* If either flag is set, both are okay, so don't check for an exact match */
    if ((req_flags & AV_TX_INPLACE) && (req_flags & FF_TX_OUT_OF_PLACE))
        req_flags &= ~(AV_TX_INPLACE | FF_TX_OUT_OF_PLACE);
    if ((req_flags & FF_TX_ALIGNED) && (req_flags & AV_TX_UNALIGNED))
        req_flags &= ~(FF_TX_ALIGNED | AV_TX_UNALIGNED);

    /* Loop through all codelets in all codelet lists to find matches
     * to the requirements */
    while (codelet_list_idx--) {
        const FFTXCodelet * const * list = codelet_list[codelet_list_idx];
        const FFTXCodelet *cd = NULL;

        while ((cd = *list++)) {
            /* Check if the type matches */
            if (cd->type != TX_TYPE_ANY && type != cd->type)
                continue;

            /* Check direction for non-orthogonal codelets */
            if (((cd->flags & FF_TX_FORWARD_ONLY) && inv) ||
                ((cd->flags & (FF_TX_INVERSE_ONLY | AV_TX_FULL_IMDCT)) && !inv) ||
                ((cd->flags & (FF_TX_FORWARD_ONLY | AV_TX_REAL_TO_REAL)) && inv) ||
                ((cd->flags & (FF_TX_FORWARD_ONLY | AV_TX_REAL_TO_IMAGINARY)) && inv))
                continue;

            /* Check if the requested flags match from both sides */
            if (((req_flags    & cd->flags) != (req_flags)) ||