PeerStreamer

/*

 * Filter layer - default implementations

 * 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

 */

#include "libavcore/audioconvert.h"

#include "libavcore/imgutils.h"

#include "libavcore/samplefmt.h"

#include "avfilter.h"

#include "internal.h"

/* TODO: buffer pool.  see comment for avfilter_default_get_video_buffer() */

void ff_avfilter_default_free_buffer(AVFilterBuffer *ptr)

{

    av_free(ptr->data[0]);

    av_free(ptr);

}

/* TODO: set the buffer's priv member to a context structure for the whole

 * filter chain.  This will allow for a buffer pool instead of the constant

 * alloc & free cycle currently implemented. */

AVFilterBufferRef *avfilter_default_get_video_buffer(AVFilterLink *link, int perms, int w, int h)

{

    int linesize[4];

    uint8_t *data[4];

    AVFilterBufferRef *picref = NULL;

    // +2 is needed for swscaler, +16 to be SIMD-friendly

    if (av_image_alloc(data, linesize, w, h, link->format, 16) < 0)

        return NULL;

    picref = avfilter_get_video_buffer_ref_from_arrays(data, linesize,

                                                       perms, w, h, link->format);

    if (!picref) {

        av_free(data[0]);

        return NULL;

    }

    return picref;

}

AVFilterBufferRef *avfilter_default_get_audio_buffer(AVFilterLink *link, int perms,

                                                     enum AVSampleFormat sample_fmt, int size,

                                                     int64_t channel_layout, int planar)

{

    AVFilterBuffer *samples = av_mallocz(sizeof(AVFilterBuffer));

    AVFilterBufferRef *ref = NULL;

    int i, sample_size, chans_nb, bufsize, per_channel_size, step_size = 0;

    char *buf;

    if (!samples || !(ref = av_mallocz(sizeof(AVFilterBufferRef))))

        goto fail;

    ref->buf                   = samples;

    ref->format                = sample_fmt;

    ref->audio = av_mallocz(sizeof(AVFilterBufferRefAudioProps));

    if (!ref->audio)

        goto fail;

    ref->audio->channel_layout = channel_layout;

    ref->audio->size           = size;

    ref->audio->planar         = planar;

    /* make sure the buffer gets read permission or it's useless for output */

    ref->perms = perms | AV_PERM_READ;

    samples->refcount   = 1;

    samples->free       = ff_avfilter_default_free_buffer;

    sample_size = av_get_bits_per_sample_fmt(sample_fmt) >>3;

    chans_nb = av_get_channel_layout_nb_channels(channel_layout);

    per_channel_size = size/chans_nb;

    ref->audio->nb_samples = per_channel_size/sample_size;

    /* Set the number of bytes to traverse to reach next sample of a particular channel:

     * For planar, this is simply the sample size.

     * For packed, this is the number of samples * sample_size.

     */

    for (i = 0; i < chans_nb; i++)

        samples->linesize[i] = planar > 0 ? per_channel_size : sample_size;

    memset(&samples->linesize[chans_nb], 0, (8-chans_nb) * sizeof(samples->linesize[0]));

    /* Calculate total buffer size, round to multiple of 16 to be SIMD friendly */

    bufsize = (size + 15)&~15;

    buf = av_malloc(bufsize);

    if (!buf)

        goto fail;

    /* For planar, set the start point of each channel's data within the buffer

     * For packed, set the start point of the entire buffer only

     */

    samples->data[0] = buf;

    if (buf && planar) {

        for (i = 1; i < chans_nb; i++) {

            step_size += per_channel_size;

            samples->data[i] = buf + step_size;

        }

    } else {

        for (i = 1; i < chans_nb; i++)

            samples->data[i] = buf;

    }

    memset(&samples->data[chans_nb], 0, (8-chans_nb) * sizeof(samples->data[0]));

    memcpy(ref->data,     samples->data,     sizeof(ref->data));

    memcpy(ref->linesize, samples->linesize, sizeof(ref->linesize));

    return ref;

fail:

    if (ref && ref->audio)

        av_free(ref->audio);

    av_free(ref);

    av_free(samples);

    return NULL;

}

void avfilter_default_start_frame(AVFilterLink *inlink, AVFilterBufferRef *picref)

{

    AVFilterLink *outlink = NULL;

    if (inlink->dst->output_count)

        outlink = inlink->dst->outputs[0];

    if (outlink) {

        outlink->out_buf = avfilter_get_video_buffer(outlink, AV_PERM_WRITE, outlink->w, outlink->h);

        avfilter_copy_buffer_ref_props(outlink->out_buf, picref);

        avfilter_start_frame(outlink, avfilter_ref_buffer(outlink->out_buf, ~0));

    }

}

void avfilter_default_draw_slice(AVFilterLink *inlink, int y, int h, int slice_dir)

{

    AVFilterLink *outlink = NULL;

    if (inlink->dst->output_count)

        outlink = inlink->dst->outputs[0];

    if (outlink)

        avfilter_draw_slice(outlink, y, h, slice_dir);

}

void avfilter_default_end_frame(AVFilterLink *inlink)

{

    AVFilterLink *outlink = NULL;

    if (inlink->dst->output_count)

        outlink = inlink->dst->outputs[0];

    avfilter_unref_buffer(inlink->cur_buf);

    inlink->cur_buf = NULL;

    if (outlink) {

        if (outlink->out_buf) {

            avfilter_unref_buffer(outlink->out_buf);

            outlink->out_buf = NULL;

        }

        avfilter_end_frame(outlink);

    }

}

/* FIXME: samplesref is same as link->cur_buf. Need to consider removing the redundant parameter. */

void avfilter_default_filter_samples(AVFilterLink *inlink, AVFilterBufferRef *samplesref)

{

    AVFilterLink *outlink = NULL;

    if (inlink->dst->output_count)

        outlink = inlink->dst->outputs[0];

    if (outlink) {

        outlink->out_buf = avfilter_default_get_audio_buffer(inlink, AV_PERM_WRITE, samplesref->format,

                                                             samplesref->audio->size,

                                                             samplesref->audio->channel_layout,

                                                             samplesref->audio->planar);

        outlink->out_buf->pts                = samplesref->pts;

        outlink->out_buf->audio->sample_rate = samplesref->audio->sample_rate;

        avfilter_filter_samples(outlink, avfilter_ref_buffer(outlink->out_buf, ~0));

        avfilter_unref_buffer(outlink->out_buf);

        outlink->out_buf = NULL;

    }

    avfilter_unref_buffer(samplesref);

    inlink->cur_buf = NULL;

}

/**

 * default config_link() implementation for output video links to simplify

 * the implementation of one input one output video filters */

int avfilter_default_config_output_link(AVFilterLink *link)

{

    if (link->src->input_count && link->src->inputs[0]) {

        if (link->type == AVMEDIA_TYPE_VIDEO) {

            link->w = link->src->inputs[0]->w;

            link->h = link->src->inputs[0]->h;

            link->time_base = link->src->inputs[0]->time_base;

        } else if (link->type == AVMEDIA_TYPE_AUDIO) {

            link->channel_layout = link->src->inputs[0]->channel_layout;

            link->sample_rate    = link->src->inputs[0]->sample_rate;

        }

    } else {

        /* XXX: any non-simple filter which would cause this branch to be taken

         * really should implement its own config_props() for this link. */

        return -1;

    }

    return 0;

}

/**

 * A helper for query_formats() which sets all links to the same list of

 * formats. If there are no links hooked to this filter, the list of formats is

 * freed.

 *

 * FIXME: this will need changed for filters with a mix of pad types

 * (video + audio, etc)

 */

void avfilter_set_common_formats(AVFilterContext *ctx, AVFilterFormats *formats)

{

    int count = 0, i;

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

        if (ctx->inputs[i]) {

            avfilter_formats_ref(formats, &ctx->inputs[i]->out_formats);

            count++;

        }

    }

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

        if (ctx->outputs[i]) {

            avfilter_formats_ref(formats, &ctx->outputs[i]->in_formats);

            count++;

        }

    }

    if (!count) {

        av_free(formats->formats);

        av_free(formats->refs);

        av_free(formats);

    }

}

int avfilter_default_query_formats(AVFilterContext *ctx)

{

    enum AVMediaType type = ctx->inputs  && ctx->inputs [0] ? ctx->inputs [0]->type :

                            ctx->outputs && ctx->outputs[0] ? ctx->outputs[0]->type :

                            AVMEDIA_TYPE_VIDEO;

    avfilter_set_common_formats(ctx, avfilter_all_formats(type));

    return 0;

}

void avfilter_null_start_frame(AVFilterLink *link, AVFilterBufferRef *picref)

{

    avfilter_start_frame(link->dst->outputs[0], picref);

}

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

{

    avfilter_draw_slice(link->dst->outputs[0], y, h, slice_dir);

}

void avfilter_null_end_frame(AVFilterLink *link)

{

    avfilter_end_frame(link->dst->outputs[0]);

}

void avfilter_null_filter_samples(AVFilterLink *link, AVFilterBufferRef *samplesref)

{

    avfilter_filter_samples(link->dst->outputs[0], samplesref);

}

AVFilterBufferRef *avfilter_null_get_video_buffer(AVFilterLink *link, int perms, int w, int h)

{

    return avfilter_get_video_buffer(link->dst->outputs[0], perms, w, h);

}

AVFilterBufferRef *avfilter_null_get_audio_buffer(AVFilterLink *link, int perms,

                                                  enum AVSampleFormat sample_fmt, int size,

                                                  int64_t channel_layout, int packed)

{

    return avfilter_get_audio_buffer(link->dst->outputs[0], perms, sample_fmt,

                                     size, channel_layout, packed);

}