PeerStreamer

/*

 * filter layer

 * copyright (c) 2007 Bobby Bingham

 *

 * This file is part of FFmpeg.

 *

 * FFmpeg is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2.1 of the License, or (at your option) any later version.

 *

 * FFmpeg is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with FFmpeg; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

 */

/* #define DEBUG */

#include "libavcodec/imgconvert.h"

#include "libavutil/pixdesc.h"

#include "avfilter.h"

unsigned avfilter_version(void) {

    return LIBAVFILTER_VERSION_INT;

}

const char *avfilter_configuration(void)

{

    return FFMPEG_CONFIGURATION;

}

const char *avfilter_license(void)

{

#define LICENSE_PREFIX "libavfilter license: "

    return LICENSE_PREFIX FFMPEG_LICENSE + sizeof(LICENSE_PREFIX) - 1;

}

/** helper macros to get the in/out pad on the dst/src filter */

#define link_dpad(link)     link->dst-> input_pads[link->dstpad]

#define link_spad(link)     link->src->output_pads[link->srcpad]

AVFilterPicRef *avfilter_ref_pic(AVFilterPicRef *ref, int pmask)

{

    AVFilterPicRef *ret = av_malloc(sizeof(AVFilterPicRef));

    *ret = *ref;

    ret->perms &= pmask;

    ret->pic->refcount ++;

    return ret;

}

void avfilter_unref_pic(AVFilterPicRef *ref)

{

    if(!(--ref->pic->refcount))

        ref->pic->free(ref->pic);

    av_free(ref);

}

void avfilter_insert_pad(unsigned idx, unsigned *count, size_t padidx_off,

                         AVFilterPad **pads, AVFilterLink ***links,

                         AVFilterPad *newpad)

{

    unsigned i;

    idx = FFMIN(idx, *count);

    *pads  = av_realloc(*pads,  sizeof(AVFilterPad)   * (*count + 1));

    *links = av_realloc(*links, sizeof(AVFilterLink*) * (*count + 1));

    memmove(*pads +idx+1, *pads +idx, sizeof(AVFilterPad)   * (*count-idx));

    memmove(*links+idx+1, *links+idx, sizeof(AVFilterLink*) * (*count-idx));

    memcpy(*pads+idx, newpad, sizeof(AVFilterPad));

    (*links)[idx] = NULL;

    (*count) ++;

    for(i = idx+1; i < *count; i ++)

        if(*links[i])

            (*(unsigned *)((uint8_t *) *links[i] + padidx_off)) ++;

}

int avfilter_link(AVFilterContext *src, unsigned srcpad,

                  AVFilterContext *dst, unsigned dstpad)

{

    AVFilterLink *link;

    if(src->output_count <= srcpad || dst->input_count <= dstpad ||

       src->outputs[srcpad]        || dst->inputs[dstpad])

        return -1;

    src->outputs[srcpad] =

    dst-> inputs[dstpad] = link = av_mallocz(sizeof(AVFilterLink));

    link->src     = src;

    link->dst     = dst;

    link->srcpad  = srcpad;

    link->dstpad  = dstpad;

    link->format  = PIX_FMT_NONE;

    return 0;

}

int avfilter_insert_filter(AVFilterLink *link, AVFilterContext *filt,

                           unsigned in, unsigned out)

{

    av_log(link->dst, AV_LOG_INFO, "auto-inserting filter '%s' "

           "between the filter '%s' and the filter '%s'\n",

           filt->name, link->src->name, link->dst->name);

    link->dst->inputs[link->dstpad] = NULL;

    if(avfilter_link(filt, out, link->dst, link->dstpad)) {

        /* failed to link output filter to new filter */

        link->dst->inputs[link->dstpad] = link;

        return -1;

    }

    /* re-hookup the link to the new destination filter we inserted */

    link->dst = filt;

    link->dstpad = in;

    filt->inputs[in] = link;

    /* if any information on supported colorspaces already exists on the

     * link, we need to preserve that */

    if(link->out_formats)

        avfilter_formats_changeref(&link->out_formats,

                                   &filt->outputs[out]->out_formats);

    return 0;

}

int avfilter_config_links(AVFilterContext *filter)

{

    int (*config_link)(AVFilterLink *);

    unsigned i;

    for(i = 0; i < filter->input_count; i ++) {

        AVFilterLink *link = filter->inputs[i];

        if(!link) continue;

        switch(link->init_state) {

        case AVLINK_INIT:

            continue;

        case AVLINK_STARTINIT:

            av_log(filter, AV_LOG_INFO, "circular filter chain detected\n");

            return 0;

        case AVLINK_UNINIT:

            link->init_state = AVLINK_STARTINIT;

            if(avfilter_config_links(link->src))

                return -1;

            if(!(config_link = link_spad(link).config_props))

                config_link  = avfilter_default_config_output_link;

            if(config_link(link))

                return -1;

            if((config_link = link_dpad(link).config_props))

                if(config_link(link))

                    return -1;

            link->init_state = AVLINK_INIT;

        }

    }

    return 0;

}

static void dprintf_picref(void *ctx, AVFilterPicRef *picref, int end)

{

    dprintf(ctx,

            "picref[%p data[%p, %p, %p, %p] linesize[%d, %d, %d, %d] pts:%"PRId64" pos:%"PRId64" a:%d/%d s:%dx%d]%s",

            picref,

            picref->data    [0], picref->data    [1], picref->data    [2], picref->data    [3],

            picref->linesize[0], picref->linesize[1], picref->linesize[2], picref->linesize[3],

            picref->pts, picref->pos,

            picref->pixel_aspect.num, picref->pixel_aspect.den, picref->w, picref->h,

            end ? "\n" : "");

}

static void dprintf_link(void *ctx, AVFilterLink *link, int end)

{

    dprintf(ctx,

            "link[%p s:%dx%d fmt:%-16s %-16s->%-16s]%s",

            link, link->w, link->h,

            av_pix_fmt_descriptors[link->format].name,

            link->src ? link->src->filter->name : "",

            link->dst ? link->dst->filter->name : "",

            end ? "\n" : "");

}

#define DPRINTF_START(ctx, func) dprintf(NULL, "%-16s: ", #func)

AVFilterPicRef *avfilter_get_video_buffer(AVFilterLink *link, int perms, int w, int h)

{

    AVFilterPicRef *ret = NULL;

    DPRINTF_START(NULL, get_video_buffer); dprintf_link(NULL, link, 0); dprintf(NULL, " perms:%d w:%d h:%d\n", perms, w, h);

    if(link_dpad(link).get_video_buffer)

        ret = link_dpad(link).get_video_buffer(link, perms, w, h);

    if(!ret)

        ret = avfilter_default_get_video_buffer(link, perms, w, h);

    DPRINTF_START(NULL, get_video_buffer); dprintf_link(NULL, link, 0); dprintf(NULL, " returning "); dprintf_picref(NULL, ret, 1);

    return ret;

}

int avfilter_request_frame(AVFilterLink *link)

{

    DPRINTF_START(NULL, request_frame); dprintf_link(NULL, link, 1);

    if(link_spad(link).request_frame)

        return link_spad(link).request_frame(link);

    else if(link->src->inputs[0])

        return avfilter_request_frame(link->src->inputs[0]);

    else return -1;

}

int avfilter_poll_frame(AVFilterLink *link)

{

    int i, min=INT_MAX;

    if(link_spad(link).poll_frame)

        return link_spad(link).poll_frame(link);

    for (i=0; i<link->src->input_count; i++) {

        int val;

        if(!link->src->inputs[i])

            return -1;

        val = avfilter_poll_frame(link->src->inputs[i]);

        min = FFMIN(min, val);

    }

    return min;

}

/* XXX: should we do the duplicating of the picture ref here, instead of

 * forcing the source filter to do it? */

void avfilter_start_frame(AVFilterLink *link, AVFilterPicRef *picref)

{

    void (*start_frame)(AVFilterLink *, AVFilterPicRef *);

    AVFilterPad *dst = &link_dpad(link);

    DPRINTF_START(NULL, start_frame); dprintf_link(NULL, link, 0); dprintf(NULL, " "); dprintf_picref(NULL, picref, 1);

    if(!(start_frame = dst->start_frame))

        start_frame = avfilter_default_start_frame;

    /* prepare to copy the picture if it has insufficient permissions */

    if((dst->min_perms & picref->perms) != dst->min_perms ||

        dst->rej_perms & picref->perms) {

        /*

        av_log(link->dst, AV_LOG_INFO,

                "frame copy needed (have perms %x, need %x, reject %x)\n",

                picref->perms,

                link_dpad(link).min_perms, link_dpad(link).rej_perms);

        */

        link->cur_pic = avfilter_default_get_video_buffer(link, dst->min_perms, link->w, link->h);

        link->srcpic = picref;

        link->cur_pic->pts = link->srcpic->pts;

        link->cur_pic->pos = link->srcpic->pos;

        link->cur_pic->pixel_aspect = link->srcpic->pixel_aspect;

        link->cur_pic->interlaced      = link->srcpic->interlaced;

        link->cur_pic->top_field_first = link->srcpic->top_field_first;

    }

    else

        link->cur_pic = picref;

    start_frame(link, link->cur_pic);

}

void avfilter_end_frame(AVFilterLink *link)

{

    void (*end_frame)(AVFilterLink *);

    if(!(end_frame = link_dpad(link).end_frame))

        end_frame = avfilter_default_end_frame;

    end_frame(link);

    /* unreference the source picture if we're feeding the destination filter

     * a copied version dues to permission issues */

    if(link->srcpic) {

        avfilter_unref_pic(link->srcpic);

        link->srcpic = NULL;

    }

}

void avfilter_draw_slice(AVFilterLink *link, int y, int h, int slice_dir)

{

    uint8_t *src[4], *dst[4];

    int i, j, vsub;

    void (*draw_slice)(AVFilterLink *, int, int, int);

    DPRINTF_START(NULL, draw_slice); dprintf_link(NULL, link, 0); dprintf(NULL, " y:%d h:%d dir:%d\n", y, h, slice_dir);

    /* copy the slice if needed for permission reasons */

    if(link->srcpic) {

        vsub = av_pix_fmt_descriptors[link->format].log2_chroma_h;

        for(i = 0; i < 4; i ++) {

            if(link->srcpic->data[i]) {

                src[i] = link->srcpic-> data[i] +

                    (y >> (i==0 ? 0 : vsub)) * link->srcpic-> linesize[i];

                dst[i] = link->cur_pic->data[i] +

                    (y >> (i==0 ? 0 : vsub)) * link->cur_pic->linesize[i];

            } else

                src[i] = dst[i] = NULL;

        }

        for(i = 0; i < 4; i ++) {

            int planew =

                ff_get_plane_bytewidth(link->format, link->cur_pic->w, i);

            if(!src[i]) continue;

            for(j = 0; j < h >> (i==0 ? 0 : vsub); j ++) {

                memcpy(dst[i], src[i], planew);

                src[i] += link->srcpic ->linesize[i];

                dst[i] += link->cur_pic->linesize[i];

            }

        }

    }

    if(!(draw_slice = link_dpad(link).draw_slice))

        draw_slice = avfilter_default_draw_slice;

    draw_slice(link, y, h, slice_dir);

}

#define MAX_REGISTERED_AVFILTERS_NB 64

static AVFilter *registered_avfilters[MAX_REGISTERED_AVFILTERS_NB + 1];

static int next_registered_avfilter_idx = 0;

AVFilter *avfilter_get_by_name(const char *name)

{

    int i;

    for (i = 0; registered_avfilters[i]; i++)

        if (!strcmp(registered_avfilters[i]->name, name))

            return registered_avfilters[i];

    return NULL;

}

int avfilter_register(AVFilter *filter)

{

    if (next_registered_avfilter_idx == MAX_REGISTERED_AVFILTERS_NB)

        return -1;

    registered_avfilters[next_registered_avfilter_idx++] = filter;

    return 0;

}

AVFilter **av_filter_next(AVFilter **filter)

{

    return filter ? ++filter : &registered_avfilters[0];

}

void avfilter_uninit(void)

{

    memset(registered_avfilters, 0, sizeof(registered_avfilters));

    next_registered_avfilter_idx = 0;

}

static int pad_count(const AVFilterPad *pads)

{

    int count;

    for(count = 0; pads->name; count ++) pads ++;

    return count;

}

static const char *filter_name(void *p)

{

    AVFilterContext *filter = p;

    return filter->filter->name;

}

static const AVClass avfilter_class = {

    "AVFilter",

    filter_name,

    NULL,

    LIBAVUTIL_VERSION_INT,

};

AVFilterContext *avfilter_open(AVFilter *filter, const char *inst_name)

{

    AVFilterContext *ret;

    if (!filter)

        return 0;

    ret = av_mallocz(sizeof(AVFilterContext));

    ret->av_class = &avfilter_class;

    ret->filter   = filter;

    ret->name     = inst_name ? av_strdup(inst_name) : NULL;

    ret->priv     = av_mallocz(filter->priv_size);

    ret->input_count  = pad_count(filter->inputs);

    if (ret->input_count) {

        ret->input_pads   = av_malloc(sizeof(AVFilterPad) * ret->input_count);

        memcpy(ret->input_pads, filter->inputs, sizeof(AVFilterPad) * ret->input_count);

        ret->inputs       = av_mallocz(sizeof(AVFilterLink*) * ret->input_count);

    }

    ret->output_count = pad_count(filter->outputs);

    if (ret->output_count) {

        ret->output_pads  = av_malloc(sizeof(AVFilterPad) * ret->output_count);

        memcpy(ret->output_pads, filter->outputs, sizeof(AVFilterPad) * ret->output_count);

        ret->outputs      = av_mallocz(sizeof(AVFilterLink*) * ret->output_count);

    }

    return ret;

}

void avfilter_destroy(AVFilterContext *filter)

{

    int i;

    if(filter->filter->uninit)

        filter->filter->uninit(filter);

    for(i = 0; i < filter->input_count; i ++) {

        if(filter->inputs[i])

            filter->inputs[i]->src->outputs[filter->inputs[i]->srcpad] = NULL;

        av_freep(&filter->inputs[i]);

    }

    for(i = 0; i < filter->output_count; i ++) {

        if(filter->outputs[i])

            filter->outputs[i]->dst->inputs[filter->outputs[i]->dstpad] = NULL;

        av_freep(&filter->outputs[i]);

    }

    av_freep(&filter->name);

    av_freep(&filter->input_pads);

    av_freep(&filter->output_pads);

    av_freep(&filter->inputs);

    av_freep(&filter->outputs);

    av_freep(&filter->priv);

    av_free(filter);

}

int avfilter_init_filter(AVFilterContext *filter, const char *args, void *opaque)

{

    int ret=0;

    if(filter->filter->init)

        ret = filter->filter->init(filter, args, opaque);

    return ret;

}