libavfilter/fifo.c - nest-android-app/ffmpeg - Git at Google

 /*
  * 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
  */

 /**
  * @file
  * FIFO buffering filter
  */

 #include "libavutil/avassert.h"
 #include "libavutil/channel_layout.h"
 #include "libavutil/common.h"
 #include "libavutil/mathematics.h"
 #include "libavutil/samplefmt.h"

 #include "audio.h"
 #include "avfilter.h"
 #include "internal.h"
 #include "video.h"

 typedef struct Buf {
     AVFrame *frame;
     struct Buf        *next;
 } Buf;

 typedef struct FifoContext {
     Buf  root;
     Buf *last;   ///< last buffered frame

     /**
      * When a specific number of output samples is requested, the partial
      * buffer is stored here
      */
     AVFrame *out;
     int allocated_samples;      ///< number of samples out was allocated for
 } FifoContext;

 static av_cold int init(AVFilterContext *ctx)
 {
     FifoContext *fifo = ctx->priv;
     fifo->last = &fifo->root;

     return 0;
 }

 static av_cold void uninit(AVFilterContext *ctx)
 {
     FifoContext *fifo = ctx->priv;
     Buf *buf, *tmp;

     for (buf = fifo->root.next; buf; buf = tmp) {
         tmp = buf->next;
         av_frame_free(&buf->frame);
         av_free(buf);
     }

     av_frame_free(&fifo->out);
 }

 static int add_to_queue(AVFilterLink *inlink, AVFrame *frame)
 {
     FifoContext *fifo = inlink->dst->priv;

     fifo->last->next = av_mallocz(sizeof(Buf));
     if (!fifo->last->next) {
         av_frame_free(&frame);
         return AVERROR(ENOMEM);
     }

     fifo->last = fifo->last->next;
     fifo->last->frame = frame;

     return 0;
 }

 static void queue_pop(FifoContext *s)
 {
     Buf *tmp = s->root.next->next;
     if (s->last == s->root.next)
         s->last = &s->root;
     av_freep(&s->root.next);
     s->root.next = tmp;
 }

 /**
  * Move data pointers and pts offset samples forward.
  */
 static void buffer_offset(AVFilterLink *link, AVFrame *frame,
                           int offset)
 {
     int nb_channels = av_get_channel_layout_nb_channels(link->channel_layout);
     int planar = av_sample_fmt_is_planar(link->format);
     int planes = planar ? nb_channels : 1;
     int block_align = av_get_bytes_per_sample(link->format) * (planar ? 1 : nb_channels);
     int i;

     av_assert0(frame->nb_samples > offset);

     for (i = 0; i < planes; i++)
         frame->extended_data[i] += block_align * offset;
     if (frame->data != frame->extended_data)
         memcpy(frame->data, frame->extended_data,
                FFMIN(planes, FF_ARRAY_ELEMS(frame->data)) * sizeof(*frame->data));
     frame->linesize[0] -= block_align*offset;
     frame->nb_samples -= offset;

     if (frame->pts != AV_NOPTS_VALUE) {
         frame->pts += av_rescale_q(offset, (AVRational){1, link->sample_rate},
                                    link->time_base);
     }
 }

 static int calc_ptr_alignment(AVFrame *frame)
 {
     int planes = av_sample_fmt_is_planar(frame->format) ?
                  av_get_channel_layout_nb_channels(frame->channel_layout) : 1;
     int min_align = 128;
     int p;

     for (p = 0; p < planes; p++) {
         int cur_align = 128;
         while ((intptr_t)frame->extended_data[p] % cur_align)
             cur_align >>= 1;
         if (cur_align < min_align)
             min_align = cur_align;
     }
     return min_align;
 }

 static int return_audio_frame(AVFilterContext *ctx)
 {
     AVFilterLink *link = ctx->outputs[0];
     FifoContext *s = ctx->priv;
     AVFrame *head = s->root.next ? s->root.next->frame : NULL;
     AVFrame *out;
     int ret;

     /* if head is NULL then we're flushing the remaining samples in out */
     if (!head && !s->out)
         return AVERROR_EOF;

     if (!s->out &&
         head->nb_samples >= link->request_samples &&
         calc_ptr_alignment(head) >= 32) {
         if (head->nb_samples == link->request_samples) {
             out = head;
             queue_pop(s);
         } else {
             out = av_frame_clone(head);
             if (!out)
                 return AVERROR(ENOMEM);

             out->nb_samples = link->request_samples;
             buffer_offset(link, head, link->request_samples);
         }
     } else {
         int nb_channels = av_get_channel_layout_nb_channels(link->channel_layout);

         if (!s->out) {
             s->out = ff_get_audio_buffer(link, link->request_samples);
             if (!s->out)
                 return AVERROR(ENOMEM);

             s->out->nb_samples = 0;
             s->out->pts                   = head->pts;
             s->allocated_samples          = link->request_samples;
         } else if (link->request_samples != s->allocated_samples) {
             av_log(ctx, AV_LOG_ERROR, "request_samples changed before the "
                    "buffer was returned.\n");
             return AVERROR(EINVAL);
         }

         while (s->out->nb_samples < s->allocated_samples) {
             int len;

             if (!s->root.next) {
                 ret = ff_request_frame(ctx->inputs[0]);
                 if (ret == AVERROR_EOF) {
                     av_samples_set_silence(s->out->extended_data,
                                            s->out->nb_samples,
                                            s->allocated_samples -
                                            s->out->nb_samples,
                                            nb_channels, link->format);
                     s->out->nb_samples = s->allocated_samples;
                     break;
                 } else if (ret < 0)
                     return ret;
                 if (!s->root.next)
                     return 0;
             }
             head = s->root.next->frame;

             len = FFMIN(s->allocated_samples - s->out->nb_samples,
                         head->nb_samples);

             av_samples_copy(s->out->extended_data, head->extended_data,
                             s->out->nb_samples, 0, len, nb_channels,
                             link->format);
             s->out->nb_samples += len;

             if (len == head->nb_samples) {
                 av_frame_free(&head);
                 queue_pop(s);
             } else {
                 buffer_offset(link, head, len);
             }
         }
         out = s->out;
         s->out = NULL;
     }
     return ff_filter_frame(link, out);
 }

 static int request_frame(AVFilterLink *outlink)
 {
     FifoContext *fifo = outlink->src->priv;
     int ret = 0;

     if (!fifo->root.next) {
         if ((ret = ff_request_frame(outlink->src->inputs[0])) < 0) {
             if (ret == AVERROR_EOF && outlink->request_samples)
                 return return_audio_frame(outlink->src);
             return ret;
         }
         if (!fifo->root.next)
             return 0;
     }

     if (outlink->request_samples) {
         return return_audio_frame(outlink->src);
     } else {
         ret = ff_filter_frame(outlink, fifo->root.next->frame);
         queue_pop(fifo);
     }

     return ret;
 }

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

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

 AVFilter ff_vf_fifo = {
     .name      = "fifo",
     .description = NULL_IF_CONFIG_SMALL("Buffer input images and send them when they are requested."),

     .init      = init,
     .uninit    = uninit,

     .priv_size = sizeof(FifoContext),

     .inputs    = avfilter_vf_fifo_inputs,
     .outputs   = avfilter_vf_fifo_outputs,
 };

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

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

 AVFilter ff_af_afifo = {
     .name        = "afifo",
     .description = NULL_IF_CONFIG_SMALL("Buffer input frames and send them when they are requested."),

     .init      = init,
     .uninit    = uninit,

     .priv_size = sizeof(FifoContext),

     .inputs    = avfilter_af_afifo_inputs,
     .outputs   = avfilter_af_afifo_outputs,
 };
	/*
	* 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
	*/

	/**
	* @file
	* FIFO buffering filter
	*/

	#include "libavutil/avassert.h"
	#include "libavutil/channel_layout.h"
	#include "libavutil/common.h"
	#include "libavutil/mathematics.h"
	#include "libavutil/samplefmt.h"

	#include "audio.h"
	#include "avfilter.h"
	#include "internal.h"
	#include "video.h"

	typedef struct Buf {
	AVFrame *frame;
	struct Buf *next;
	} Buf;

	typedef struct FifoContext {
	Buf root;
	Buf *last; ///< last buffered frame

	/**
	* When a specific number of output samples is requested, the partial
	* buffer is stored here
	*/
	AVFrame *out;
	int allocated_samples; ///< number of samples out was allocated for
	} FifoContext;

	static av_cold int init(AVFilterContext *ctx)
	{
	FifoContext *fifo = ctx->priv;
	fifo->last = &fifo->root;

	return 0;
	}

	static av_cold void uninit(AVFilterContext *ctx)
	{
	FifoContext *fifo = ctx->priv;
	Buf buf, tmp;

	for (buf = fifo->root.next; buf; buf = tmp) {
	tmp = buf->next;
	av_frame_free(&buf->frame);
	av_free(buf);
	}

	av_frame_free(&fifo->out);
	}

	static int add_to_queue(AVFilterLink inlink, AVFrame frame)
	{
	FifoContext *fifo = inlink->dst->priv;

	fifo->last->next = av_mallocz(sizeof(Buf));
	if (!fifo->last->next) {
	av_frame_free(&frame);
	return AVERROR(ENOMEM);
	}

	fifo->last = fifo->last->next;
	fifo->last->frame = frame;

	return 0;
	}

	static void queue_pop(FifoContext *s)
	{
	Buf *tmp = s->root.next->next;
	if (s->last == s->root.next)
	s->last = &s->root;
	av_freep(&s->root.next);
	s->root.next = tmp;
	}

	/**
	* Move data pointers and pts offset samples forward.
	*/
	static void buffer_offset(AVFilterLink link, AVFrame frame,
	int offset)
	{
	int nb_channels = av_get_channel_layout_nb_channels(link->channel_layout);
	int planar = av_sample_fmt_is_planar(link->format);
	int planes = planar ? nb_channels : 1;
	int block_align = av_get_bytes_per_sample(link->format) * (planar ? 1 : nb_channels);
	int i;

	av_assert0(frame->nb_samples > offset);

	for (i = 0; i < planes; i++)
	frame->extended_data[i] += block_align * offset;
	if (frame->data != frame->extended_data)
	memcpy(frame->data, frame->extended_data,
	FFMIN(planes, FF_ARRAY_ELEMS(frame->data)) * sizeof(*frame->data));
	frame->linesize[0] -= block_align*offset;
	frame->nb_samples -= offset;

	if (frame->pts != AV_NOPTS_VALUE) {
	frame->pts += av_rescale_q(offset, (AVRational){1, link->sample_rate},
	link->time_base);
	}
	}

	static int calc_ptr_alignment(AVFrame *frame)
	{
	int planes = av_sample_fmt_is_planar(frame->format) ?
	av_get_channel_layout_nb_channels(frame->channel_layout) : 1;
	int min_align = 128;
	int p;

	for (p = 0; p < planes; p++) {
	int cur_align = 128;
	while ((intptr_t)frame->extended_data[p] % cur_align)
	cur_align >>= 1;
	if (cur_align < min_align)
	min_align = cur_align;
	}
	return min_align;
	}

	static int return_audio_frame(AVFilterContext *ctx)
	{
	AVFilterLink *link = ctx->outputs[0];
	FifoContext *s = ctx->priv;
	AVFrame *head = s->root.next ? s->root.next->frame : NULL;
	AVFrame *out;
	int ret;

	/* if head is NULL then we're flushing the remaining samples in out */
	if (!head && !s->out)
	return AVERROR_EOF;

	if (!s->out &&
	head->nb_samples >= link->request_samples &&
	calc_ptr_alignment(head) >= 32) {
	if (head->nb_samples == link->request_samples) {
	out = head;
	queue_pop(s);
	} else {
	out = av_frame_clone(head);
	if (!out)
	return AVERROR(ENOMEM);

	out->nb_samples = link->request_samples;
	buffer_offset(link, head, link->request_samples);
	}
	} else {
	int nb_channels = av_get_channel_layout_nb_channels(link->channel_layout);

	if (!s->out) {
	s->out = ff_get_audio_buffer(link, link->request_samples);
	if (!s->out)
	return AVERROR(ENOMEM);

	s->out->nb_samples = 0;
	s->out->pts = head->pts;
	s->allocated_samples = link->request_samples;
	} else if (link->request_samples != s->allocated_samples) {
	av_log(ctx, AV_LOG_ERROR, "request_samples changed before the "
	"buffer was returned.\n");
	return AVERROR(EINVAL);
	}

	while (s->out->nb_samples < s->allocated_samples) {
	int len;

	if (!s->root.next) {
	ret = ff_request_frame(ctx->inputs[0]);
	if (ret == AVERROR_EOF) {
	av_samples_set_silence(s->out->extended_data,
	s->out->nb_samples,
	s->allocated_samples -
	s->out->nb_samples,
	nb_channels, link->format);
	s->out->nb_samples = s->allocated_samples;
	break;
	} else if (ret < 0)
	return ret;
	if (!s->root.next)
	return 0;
	}
	head = s->root.next->frame;

	len = FFMIN(s->allocated_samples - s->out->nb_samples,
	head->nb_samples);

	av_samples_copy(s->out->extended_data, head->extended_data,
	s->out->nb_samples, 0, len, nb_channels,
	link->format);
	s->out->nb_samples += len;

	if (len == head->nb_samples) {
	av_frame_free(&head);
	queue_pop(s);
	} else {
	buffer_offset(link, head, len);
	}
	}
	out = s->out;
	s->out = NULL;
	}
	return ff_filter_frame(link, out);
	}

	static int request_frame(AVFilterLink *outlink)
	{
	FifoContext *fifo = outlink->src->priv;
	int ret = 0;

	if (!fifo->root.next) {
	if ((ret = ff_request_frame(outlink->src->inputs[0])) < 0) {
	if (ret == AVERROR_EOF && outlink->request_samples)
	return return_audio_frame(outlink->src);
	return ret;
	}
	if (!fifo->root.next)
	return 0;
	}

	if (outlink->request_samples) {
	return return_audio_frame(outlink->src);
	} else {
	ret = ff_filter_frame(outlink, fifo->root.next->frame);
	queue_pop(fifo);
	}

	return ret;
	}

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

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

	AVFilter ff_vf_fifo = {
	.name = "fifo",
	.description = NULL_IF_CONFIG_SMALL("Buffer input images and send them when they are requested."),

	.init = init,
	.uninit = uninit,

	.priv_size = sizeof(FifoContext),

	.inputs = avfilter_vf_fifo_inputs,
	.outputs = avfilter_vf_fifo_outputs,
	};

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

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

	AVFilter ff_af_afifo = {
	.name = "afifo",
	.description = NULL_IF_CONFIG_SMALL("Buffer input frames and send them when they are requested."),

	.init = init,
	.uninit = uninit,

	.priv_size = sizeof(FifoContext),

	.inputs = avfilter_af_afifo_inputs,
	.outputs = avfilter_af_afifo_outputs,
	};