af_ladspa.c

自己移植的linux下的流媒体播放器原代码,支持mms协议,支持ftp和http协议.

                af_msg(AF_MSG_ERROR, MSGTR_AF_LADSPA_ErrControlBelow,
                                            setup->myname, i, hint.LowerBound);
                return AF_ERROR;
            }
            if (LADSPA_IS_HINT_BOUNDED_ABOVE(hint.HintDescriptor) &&
                    val > hint.UpperBound) {
                af_msg(AF_MSG_ERROR, MSGTR_AF_LADSPA_ErrControlAbove,
                                            setup->myname, i, hint.UpperBound);
                return AF_ERROR;
            }
        }
        af_msg(AF_MSG_VERBOSE, "%s: all controls have sane values\n",
                                                                setup->myname);

        /* All is well! */
        setup->status = AF_OK;

        return AF_OK; }
    }

    return AF_UNKNOWN;
}

/* ------------------------------------------------------------------------- */

/** \brief Uninitialise the LADSPA Plugin Loader filter.
 *
 * This function deactivates the plugin(s), cleans up, frees all allocated
 * memory and exits.
 *
 * \return  No return value.
 */

static void uninit(struct af_instance_s *af) {
    int i;

    if (af->data)
        free(af->data);
    if (af->setup) {
        af_ladspa_t *setup = (af_ladspa_t*) af->setup;
        const LADSPA_Descriptor *pdes = setup->plugin_descriptor;

        if (setup->myname) {
            af_msg(AF_MSG_VERBOSE, "%s: cleaning up\n", setup->myname);
            free(setup->myname);
        }

        if (setup->chhandles) {
            for(i=0; i<setup->nch; i++) {
                if ( (setup->ninputs == 2) && (i & 1) ) { /* stereo effect */
                    i++;
                    continue;
                }
                if (pdes->deactivate) pdes->deactivate(setup->chhandles[i]);
                if (pdes->cleanup) pdes->cleanup(setup->chhandles[i]);
            }
            free(setup->chhandles);
        }

        if (setup->file)
            free(setup->file);
        if (setup->label)
            free(setup->label);
        if (setup->inputcontrolsmap)
            free(setup->inputcontrolsmap);
        if (setup->inputcontrols)
            free(setup->inputcontrols);
        if (setup->outputcontrolsmap)
            free(setup->outputcontrolsmap);
        if (setup->outputcontrols)
            free(setup->outputcontrols);
        if (setup->inputs)
            free(setup->inputs);
        if (setup->outputs)
            free(setup->outputs);

        if (setup->inbufs) {
            for(i=0; i<setup->nch; i++) {
                if (setup->inbufs[i])
                    free(setup->inbufs[i]);
            }
            free(setup->inbufs);
        }

        if (setup->outbufs) {
            for(i=0; i<setup->nch; i++) {
                if (setup->outbufs[i])
                    free(setup->outbufs[i]);
            }
            free(setup->outbufs);
        }

        if (setup->libhandle)
            dlclose(setup->libhandle);

        free(setup);
        setup = NULL;
    }
}

/* ------------------------------------------------------------------------- */

/** \brief Process chunk of audio data through the selected LADSPA Plugin.
 * 
 * \param af    Pointer to audio filter instance
 * \param data  Pointer to chunk of audio data
 *
 * \return      Either AF_ERROR or AF_OK
 */

static af_data_t* play(struct af_instance_s *af, af_data_t *data) {
    af_ladspa_t *setup = af->setup;
    const LADSPA_Descriptor *pdes = setup->plugin_descriptor;
    int16_t *audio = (int16_t*)data->audio;
    int nsamples = data->len/2; /* /2 because it's int16_t */
    int nch = data->nch;
    int rate = data->rate;
    int i, p; 
    float v;

    if (setup->status !=AF_OK)
        return data;

    /* See if it's the first call. If so, setup inbufs/outbufs, instantiate
     * plugin, connect ports and activate plugin
     */

    /* 2004-12-07: Also check if the buffersize has to be changed!
     *             data->len is not constant per se! re-init buffers.
     */

    if ( (setup->bufsize != nsamples/nch) || (setup->nch != nch) ) {

        /* if setup->nch==0, it's the first call, if not, something has
         * changed and all previous mallocs have to be freed
         */

        if (setup->nch != 0) {
            af_msg(AF_MSG_DEBUG1, "%s: bufsize change; free old buffer\n",
                                                                setup->myname);

            if(setup->inbufs) {
                for(i=0; i<setup->nch; i++) {
                    if(setup->inbufs[i])
                        free(setup->inbufs[i]);
                }
                free(setup->inbufs);
            }
            if(setup->outbufs) {
                for(i=0; i<setup->nch; i++) {
                    if(setup->outbufs[i])
                        free(setup->outbufs[i]);
                }
                free(setup->outbufs);
            }
        } /* everything is freed */

        setup->bufsize = nsamples/nch;
        setup->nch = nch;

        setup->inbufs = calloc(nch, sizeof(float*));
        setup->outbufs = calloc(nch, sizeof(float*));

        af_msg(AF_MSG_DEBUG1, "%s: bufsize = %d\n",
                                        setup->myname, setup->bufsize);

        for(i=0; i<nch; i++) {
            setup->inbufs[i] = calloc(setup->bufsize, sizeof(float));
            setup->outbufs[i] = calloc(setup->bufsize, sizeof(float));
        }

        /* only on the first call, there are no handles. */

        if (!setup->chhandles) {
            setup->chhandles = calloc(nch, sizeof(LADSPA_Handle));

            /* create handles
             * for stereo effects, create one handle for two channels
             */

            for(i=0; i<nch; i++) {

                if ( (setup->ninputs == 2) && (i & 1) ) { /* stereo effect */
                    /* copy the handle from previous channel */
                    setup->chhandles[i] = setup->chhandles[i-1];
                    continue;
                }

                setup->chhandles[i] = pdes->instantiate(pdes, rate);
            }
        }

        /* connect input/output ports for each channel/filter instance
         *
         * always (re)connect ports
         */

        for(i=0; i<nch; i++) {
            pdes->connect_port(setup->chhandles[i],
                               setup->inputs[ (setup->ninputs==2) ? i&1 : 0 ],
                               setup->inbufs[i]);
            pdes->connect_port(setup->chhandles[i],
                               setup->outputs[ (setup->ninputs==2) ? i&1 : 0 ],
                               setup->outbufs[i]);

            /* connect (input) controls */

            for (p=0; p<setup->nports; p++) {
                LADSPA_PortDescriptor d = pdes->PortDescriptors[p];
                if (LADSPA_IS_PORT_CONTROL(d)) {
                    if (LADSPA_IS_PORT_INPUT(d)) {
                        pdes->connect_port(setup->chhandles[i], p,
                                                &(setup->inputcontrols[p]) );
                    } else {
                        pdes->connect_port(setup->chhandles[i], p,
                                                &(setup->outputcontrols[p]) );
                    }
                }
            }

            /* Activate filter (if it isn't already :) ) */

            if ( (pdes->activate) && (setup->activated == 0) ) {
                pdes->activate(setup->chhandles[i]);
                setup->activated = 1;
            }

        } /* All channels/filters done! except for... */

        /* Stereo effect with one channel left. Use same buffer for left
         * and right. connect it to the second port.
         */

        if( (setup->ninputs == 2) && (i&1) && (i >= 1) ) { 
            pdes->connect_port(setup->chhandles[i-1],
                               setup->inputs[ (setup->ninputs==2) ? i&1 : 0 ],
                               setup->inbufs[i-1]);
            pdes->connect_port(setup->chhandles[i-1],
                               setup->outputs[ (setup->ninputs==2) ? i&1 : 0 ],
                               setup->outbufs[i-1]);
        } /* done! */

    } /* setup for first call/change of bufsize is done.
       * normal playing routine follows...
       */

    /* Right now, I use a separate input and output buffer.
     * I could change this to in-place processing (inbuf==outbuf), but some
     * ladspa filters are broken and are not able to handle that. This seems
     * fast enough, so unless somebody complains, it stays this way :)
     */

    /* Fill inbufs */

    for (p=0; p<setup->bufsize; p++) {
        for (i=0; i<nch; i++) {
            setup->inbufs[i][p] = ( (float) audio[p*nch + i] ) / 32768.0f;
        }
    }

    /* Run filter(s) */

    for (i=0; i<nch; i++) {
        pdes->run(setup->chhandles[i], setup->bufsize);
        if (setup->ninputs==2) // stereo effect just ran
            i++;
    }

    /* Extract outbufs, hard clipping in case the filter exceeded [-1.0,1.0] */

    for (p=0; p<setup->bufsize; p++) {
        for (i=0; i<nch; i++) {
            v = setup->outbufs[i][p];
            v *= 32768.0f;
            v = (v > 32767.0f ? 32767.0f : v);
            v = (v < -32768.0f ? -32768.0f : v);
            audio[p*nch + i] = (int16_t) v;
        }
    }

    /* done */

    return data;
}

/* ------------------------------------------------------------------------- */

/** \brief Open LADSPA Plugin Loader Filter
 *
 * \param af    Audio Filter instance
 *
 * \return      Either AF_ERROR or AF_OK
 */

static int open(af_instance_t *af) {

    af->control=control;
    af->uninit=uninit;
    af->play=play;
    af->mul.n=1;
    af->mul.d=1;

    af->data = calloc(1, sizeof(af_data_t));
    if (af->data == NULL)
        return af_ladspa_malloc_failed((char*)af_info_ladspa.name);

    af->setup = calloc(1, sizeof(af_ladspa_t));
    if (af->setup == NULL) {
        free(af->data);
        af->data=NULL;
        return af_ladspa_malloc_failed((char*)af_info_ladspa.name);
    }

    ((af_ladspa_t*)af->setup)->status = AF_ERROR; /* will be set to AF_OK if
                                                   * all went OK and play()
                                                   * should proceed.
                                                   */

    ((af_ladspa_t*)af->setup)->myname = strdup(af_info_ladspa.name);
    if (!((af_ladspa_t*)af->setup)->myname)
        return af_ladspa_malloc_failed((char*)af_info_ladspa.name);

    return AF_OK;
}

/* ------------------------------------------------------------------------- */