FFmpeg4/libavfilter/buffersink.c

/*
 * Copyright (c) 2011 Stefano Sabatini
 *
 * 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
 */

/**
 * @file
 * buffer sink
 */

#include "libavutil/avassert.h"
#include "libavutil/channel_layout.h"
#include "libavutil/common.h"
#include "libavutil/internal.h"
#include "libavutil/opt.h"

#define FF_INTERNAL_FIELDS 1
#include "framequeue.h"

#include "audio.h"
#include "avfilter.h"
#include "buffersink.h"
#include "filters.h"
#include "internal.h"

typedef struct BufferSinkContext {
    const AVClass *class;
    unsigned warning_limit;

    /* only used for video */
    enum AVPixelFormat *pixel_fmts;           ///< list of accepted pixel formats, must be terminated with -1
    int pixel_fmts_size;

    /* only used for audio */
    enum AVSampleFormat *sample_fmts;       ///< list of accepted sample formats, terminated by AV_SAMPLE_FMT_NONE
    int sample_fmts_size;
    int64_t *channel_layouts;               ///< list of accepted channel layouts, terminated by -1
    int channel_layouts_size;
    int *channel_counts;                    ///< list of accepted channel counts, terminated by -1
    int channel_counts_size;
    int all_channel_counts;
    int *sample_rates;                      ///< list of accepted sample rates, terminated by -1
    int sample_rates_size;

    AVFrame *peeked_frame;
} BufferSinkContext;

#define NB_ITEMS(list) (list ## _size / sizeof(*list))

int attribute_align_arg av_buffersink_get_frame(AVFilterContext *ctx, AVFrame *frame)
{
    return av_buffersink_get_frame_flags(ctx, frame, 0);
}

static int return_or_keep_frame(BufferSinkContext *buf, AVFrame *out, AVFrame *in, int flags)
{
    if ((flags & AV_BUFFERSINK_FLAG_PEEK)) {
        buf->peeked_frame = in;
        return out ? av_frame_ref(out, in) : 0;
    } else {
        av_assert1(out);
        buf->peeked_frame = NULL;
        av_frame_move_ref(out, in);
        av_frame_free(&in);
        return 0;
    }
}

static int get_frame_internal(AVFilterContext *ctx, AVFrame *frame, int flags, int samples)
{
    BufferSinkContext *buf = ctx->priv;
    AVFilterLink *inlink = ctx->inputs[0];
    int status, ret;
    AVFrame *cur_frame;
    int64_t pts;

    if (buf->peeked_frame)
        return return_or_keep_frame(buf, frame, buf->peeked_frame, flags);

    while (1) {
        ret = samples ? ff_inlink_consume_samples(inlink, samples, samples, &cur_frame) :
                        ff_inlink_consume_frame(inlink, &cur_frame);
        if (ret < 0) {
            return ret;
        } else if (ret) {
            /* TODO return the frame instead of copying it */
            return return_or_keep_frame(buf, frame, cur_frame, flags);
        } else if (ff_inlink_acknowledge_status(inlink, &status, &pts)) {
            return status;
        } else if ((flags & AV_BUFFERSINK_FLAG_NO_REQUEST)) {
            return AVERROR(EAGAIN);
        } else if (inlink->frame_wanted_out) {
            ret = ff_filter_graph_run_once(ctx->graph);
            if (ret < 0)
                return ret;
        } else {
            ff_inlink_request_frame(inlink);
        }
    }
}

int attribute_align_arg av_buffersink_get_frame_flags(AVFilterContext *ctx, AVFrame *frame, int flags)
{
    return get_frame_internal(ctx, frame, flags, ctx->inputs[0]->min_samples);
}

int attribute_align_arg av_buffersink_get_samples(AVFilterContext *ctx,
                                                  AVFrame *frame, int nb_samples)
{
    return get_frame_internal(ctx, frame, 0, nb_samples);
}

#if FF_API_NEXT
AVBufferSinkParams *av_buffersink_params_alloc(void)
{
    static const int pixel_fmts[] = { AV_PIX_FMT_NONE };
    AVBufferSinkParams *params = av_malloc(sizeof(AVBufferSinkParams));
    if (!params)
        return NULL;

    params->pixel_fmts = pixel_fmts;
    return params;
}

AVABufferSinkParams *av_abuffersink_params_alloc(void)
{
    AVABufferSinkParams *params = av_mallocz(sizeof(AVABufferSinkParams));

    if (!params)
        return NULL;
    return params;
}
#endif

static av_cold int common_init(AVFilterContext *ctx)
{
    BufferSinkContext *buf = ctx->priv;

    buf->warning_limit = 100;
    return 0;
}

static int activate(AVFilterContext *ctx)
{
    BufferSinkContext *buf = ctx->priv;

    if (buf->warning_limit &&
        ff_framequeue_queued_frames(&ctx->inputs[0]->fifo) >= buf->warning_limit) {
        av_log(ctx, AV_LOG_WARNING,
               "%d buffers queued in %s, something may be wrong.\n",
               buf->warning_limit,
               (char *)av_x_if_null(ctx->name, ctx->filter->name));
        buf->warning_limit *= 10;
    }

    /* The frame is queued, the rest is up to get_frame_internal */
    return 0;
}

void av_buffersink_set_frame_size(AVFilterContext *ctx, unsigned frame_size)
{
    AVFilterLink *inlink = ctx->inputs[0];

    inlink->min_samples = inlink->max_samples =
    inlink->partial_buf_size = frame_size;
}

#define MAKE_AVFILTERLINK_ACCESSOR(type, field) \
type av_buffersink_get_##field(const AVFilterContext *ctx) { \
    av_assert0(ctx->filter->activate == activate); \
    return ctx->inputs[0]->field; \
}

MAKE_AVFILTERLINK_ACCESSOR(enum AVMediaType , type               )
MAKE_AVFILTERLINK_ACCESSOR(AVRational       , time_base          )
MAKE_AVFILTERLINK_ACCESSOR(int              , format             )

MAKE_AVFILTERLINK_ACCESSOR(AVRational       , frame_rate         )
MAKE_AVFILTERLINK_ACCESSOR(int              , w                  )
MAKE_AVFILTERLINK_ACCESSOR(int              , h                  )
MAKE_AVFILTERLINK_ACCESSOR(AVRational       , sample_aspect_ratio)

MAKE_AVFILTERLINK_ACCESSOR(int              , channels           )
MAKE_AVFILTERLINK_ACCESSOR(uint64_t         , channel_layout     )
MAKE_AVFILTERLINK_ACCESSOR(int              , sample_rate        )

MAKE_AVFILTERLINK_ACCESSOR(AVBufferRef *    , hw_frames_ctx      )

#define CHECK_LIST_SIZE(field) \
        if (buf->field ## _size % sizeof(*buf->field)) { \
            av_log(ctx, AV_LOG_ERROR, "Invalid size for " #field ": %d, " \
                   "should be multiple of %d\n", \
                   buf->field ## _size, (int)sizeof(*buf->field)); \
            return AVERROR(EINVAL); \
        }
static int vsink_query_formats(AVFilterContext *ctx)
{
    BufferSinkContext *buf = ctx->priv;
    AVFilterFormats *formats = NULL;
    unsigned i;
    int ret;

    CHECK_LIST_SIZE(pixel_fmts)
    if (buf->pixel_fmts_size) {
        for (i = 0; i < NB_ITEMS(buf->pixel_fmts); i++)
            if ((ret = ff_add_format(&formats, buf->pixel_fmts[i])) < 0)
                return ret;
        if ((ret = ff_set_common_formats(ctx, formats)) < 0)
            return ret;
    } else {
        if ((ret = ff_default_query_formats(ctx)) < 0)
            return ret;
    }

    return 0;
}

static int asink_query_formats(AVFilterContext *ctx)
{
    BufferSinkContext *buf = ctx->priv;
    AVFilterFormats *formats = NULL;
    AVFilterChannelLayouts *layouts = NULL;
    unsigned i;
    int ret;

    CHECK_LIST_SIZE(sample_fmts)
    CHECK_LIST_SIZE(sample_rates)
    CHECK_LIST_SIZE(channel_layouts)
    CHECK_LIST_SIZE(channel_counts)

    if (buf->sample_fmts_size) {
        for (i = 0; i < NB_ITEMS(buf->sample_fmts); i++)
            if ((ret = ff_add_format(&formats, buf->sample_fmts[i])) < 0)
                return ret;
        if ((ret = ff_set_common_formats(ctx, formats)) < 0)
            return ret;
    }

    if (buf->channel_layouts_size || buf->channel_counts_size ||
        buf->all_channel_counts) {
        for (i = 0; i < NB_ITEMS(buf->channel_layouts); i++)
            if ((ret = ff_add_channel_layout(&layouts, buf->channel_layouts[i])) < 0)
                return ret;
        for (i = 0; i < NB_ITEMS(buf->channel_counts); i++)
            if ((ret = ff_add_channel_layout(&layouts, FF_COUNT2LAYOUT(buf->channel_counts[i]))) < 0)
                return ret;
        if (buf->all_channel_counts) {
            if (layouts)
                av_log(ctx, AV_LOG_WARNING,
                       "Conflicting all_channel_counts and list in options\n");
            else if (!(layouts = ff_all_channel_counts()))
                return AVERROR(ENOMEM);
        }
        if ((ret = ff_set_common_channel_layouts(ctx, layouts)) < 0)
            return ret;
    }

    if (buf->sample_rates_size) {
        formats = NULL;
        for (i = 0; i < NB_ITEMS(buf->sample_rates); i++)
            if ((ret = ff_add_format(&formats, buf->sample_rates[i])) < 0)
                return ret;
        if ((ret = ff_set_common_samplerates(ctx, formats)) < 0)
            return ret;
    }

    return 0;
}

#define OFFSET(x) offsetof(BufferSinkContext, x)
#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
static const AVOption buffersink_options[] = {
    { "pix_fmts", "set the supported pixel formats", OFFSET(pixel_fmts), AV_OPT_TYPE_BINARY, .flags = FLAGS },
    { NULL },
};
#undef FLAGS
#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_AUDIO_PARAM
static const AVOption abuffersink_options[] = {
    { "sample_fmts",     "set the supported sample formats",  OFFSET(sample_fmts),     AV_OPT_TYPE_BINARY, .flags = FLAGS },
    { "sample_rates",    "set the supported sample rates",    OFFSET(sample_rates),    AV_OPT_TYPE_BINARY, .flags = FLAGS },
    { "channel_layouts", "set the supported channel layouts", OFFSET(channel_layouts), AV_OPT_TYPE_BINARY, .flags = FLAGS },
    { "channel_counts",  "set the supported channel counts",  OFFSET(channel_counts),  AV_OPT_TYPE_BINARY, .flags = FLAGS },
    { "all_channel_counts", "accept all channel counts", OFFSET(all_channel_counts), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, FLAGS },
    { NULL },
};
#undef FLAGS

AVFILTER_DEFINE_CLASS(buffersink);
AVFILTER_DEFINE_CLASS(abuffersink);

static const AVFilterPad avfilter_vsink_buffer_inputs[] = {
    {
        .name = "default",
        .type = AVMEDIA_TYPE_VIDEO,
    },
    { NULL }
};

AVFilter ff_vsink_buffer = {
    .name          = "buffersink",
    .description   = NULL_IF_CONFIG_SMALL("Buffer video frames, and make them available to the end of the filter graph."),
    .priv_size     = sizeof(BufferSinkContext),
    .priv_class    = &buffersink_class,
    .init          = common_init,
    .query_formats = vsink_query_formats,
    .activate      = activate,
    .inputs        = avfilter_vsink_buffer_inputs,
    .outputs       = NULL,
};

static const AVFilterPad avfilter_asink_abuffer_inputs[] = {
    {
        .name = "default",
        .type = AVMEDIA_TYPE_AUDIO,
    },
    { NULL }
};

AVFilter ff_asink_abuffer = {
    .name          = "abuffersink",
    .description   = NULL_IF_CONFIG_SMALL("Buffer audio frames, and make them available to the end of the filter graph."),
    .priv_class    = &abuffersink_class,
    .priv_size     = sizeof(BufferSinkContext),
    .init          = common_init,
    .query_formats = asink_query_formats,
    .activate      = activate,
    .inputs        = avfilter_asink_abuffer_inputs,
    .outputs       = NULL,
};