yading@10: /*
yading@10:  * Copyright (c) 2007 Bobby Bingham
yading@10:  *
yading@10:  * This file is part of FFmpeg.
yading@10:  *
yading@10:  * FFmpeg is free software; you can redistribute it and/or
yading@10:  * modify it under the terms of the GNU Lesser General Public
yading@10:  * License as published by the Free Software Foundation; either
yading@10:  * version 2.1 of the License, or (at your option) any later version.
yading@10:  *
yading@10:  * FFmpeg is distributed in the hope that it will be useful,
yading@10:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@10:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@10:  * Lesser General Public License for more details.
yading@10:  *
yading@10:  * You should have received a copy of the GNU Lesser General Public
yading@10:  * License along with FFmpeg; if not, write to the Free Software
yading@10:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@10:  */
yading@10: 
yading@10: /**
yading@10:  * @file
yading@10:  * FIFO buffering filter
yading@10:  */
yading@10: 
yading@10: #include "libavutil/avassert.h"
yading@10: #include "libavutil/channel_layout.h"
yading@10: #include "libavutil/common.h"
yading@10: #include "libavutil/mathematics.h"
yading@10: #include "libavutil/samplefmt.h"
yading@10: 
yading@10: #include "audio.h"
yading@10: #include "avfilter.h"
yading@10: #include "internal.h"
yading@10: #include "video.h"
yading@10: 
yading@10: typedef struct Buf {
yading@10:     AVFrame *frame;
yading@10:     struct Buf        *next;
yading@10: } Buf;
yading@10: 
yading@10: typedef struct {
yading@10:     Buf  root;
yading@10:     Buf *last;   ///< last buffered frame
yading@10: 
yading@10:     /**
yading@10:      * When a specific number of output samples is requested, the partial
yading@10:      * buffer is stored here
yading@10:      */
yading@10:     AVFrame *out;
yading@10:     int allocated_samples;      ///< number of samples out was allocated for
yading@10: } FifoContext;
yading@10: 
yading@10: static av_cold int init(AVFilterContext *ctx)
yading@10: {
yading@10:     FifoContext *fifo = ctx->priv;
yading@10:     fifo->last = &fifo->root;
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: static av_cold void uninit(AVFilterContext *ctx)
yading@10: {
yading@10:     FifoContext *fifo = ctx->priv;
yading@10:     Buf *buf, *tmp;
yading@10: 
yading@10:     for (buf = fifo->root.next; buf; buf = tmp) {
yading@10:         tmp = buf->next;
yading@10:         av_frame_free(&buf->frame);
yading@10:         av_free(buf);
yading@10:     }
yading@10: 
yading@10:     av_frame_free(&fifo->out);
yading@10: }
yading@10: 
yading@10: static int add_to_queue(AVFilterLink *inlink, AVFrame *frame)
yading@10: {
yading@10:     FifoContext *fifo = inlink->dst->priv;
yading@10: 
yading@10:     fifo->last->next = av_mallocz(sizeof(Buf));
yading@10:     if (!fifo->last->next) {
yading@10:         av_frame_free(&frame);
yading@10:         return AVERROR(ENOMEM);
yading@10:     }
yading@10: 
yading@10:     fifo->last = fifo->last->next;
yading@10:     fifo->last->frame = frame;
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: static void queue_pop(FifoContext *s)
yading@10: {
yading@10:     Buf *tmp = s->root.next->next;
yading@10:     if (s->last == s->root.next)
yading@10:         s->last = &s->root;
yading@10:     av_freep(&s->root.next);
yading@10:     s->root.next = tmp;
yading@10: }
yading@10: 
yading@10: /**
yading@10:  * Move data pointers and pts offset samples forward.
yading@10:  */
yading@10: static void buffer_offset(AVFilterLink *link, AVFrame *frame,
yading@10:                           int offset)
yading@10: {
yading@10:     int nb_channels = av_get_channel_layout_nb_channels(link->channel_layout);
yading@10:     int planar = av_sample_fmt_is_planar(link->format);
yading@10:     int planes = planar ? nb_channels : 1;
yading@10:     int block_align = av_get_bytes_per_sample(link->format) * (planar ? 1 : nb_channels);
yading@10:     int i;
yading@10: 
yading@10:     av_assert0(frame->nb_samples > offset);
yading@10: 
yading@10:     for (i = 0; i < planes; i++)
yading@10:         frame->extended_data[i] += block_align * offset;
yading@10:     if (frame->data != frame->extended_data)
yading@10:         memcpy(frame->data, frame->extended_data,
yading@10:                FFMIN(planes, FF_ARRAY_ELEMS(frame->data)) * sizeof(*frame->data));
yading@10:     frame->linesize[0] -= block_align*offset;
yading@10:     frame->nb_samples -= offset;
yading@10: 
yading@10:     if (frame->pts != AV_NOPTS_VALUE) {
yading@10:         frame->pts += av_rescale_q(offset, (AVRational){1, link->sample_rate},
yading@10:                                    link->time_base);
yading@10:     }
yading@10: }
yading@10: 
yading@10: static int calc_ptr_alignment(AVFrame *frame)
yading@10: {
yading@10:     int planes = av_sample_fmt_is_planar(frame->format) ?
yading@10:                  av_get_channel_layout_nb_channels(frame->channel_layout) : 1;
yading@10:     int min_align = 128;
yading@10:     int p;
yading@10: 
yading@10:     for (p = 0; p < planes; p++) {
yading@10:         int cur_align = 128;
yading@10:         while ((intptr_t)frame->extended_data[p] % cur_align)
yading@10:             cur_align >>= 1;
yading@10:         if (cur_align < min_align)
yading@10:             min_align = cur_align;
yading@10:     }
yading@10:     return min_align;
yading@10: }
yading@10: 
yading@10: static int return_audio_frame(AVFilterContext *ctx)
yading@10: {
yading@10:     AVFilterLink *link = ctx->outputs[0];
yading@10:     FifoContext *s = ctx->priv;
yading@10:     AVFrame *head = s->root.next->frame;
yading@10:     AVFrame *out;
yading@10:     int ret;
yading@10: 
yading@10:     if (!s->out &&
yading@10:         head->nb_samples >= link->request_samples &&
yading@10:         calc_ptr_alignment(head) >= 32) {
yading@10:         if (head->nb_samples == link->request_samples) {
yading@10:             out = head;
yading@10:             queue_pop(s);
yading@10:         } else {
yading@10:             out = av_frame_clone(head);
yading@10:             if (!out)
yading@10:                 return AVERROR(ENOMEM);
yading@10: 
yading@10:             out->nb_samples = link->request_samples;
yading@10:             buffer_offset(link, head, link->request_samples);
yading@10:         }
yading@10:     } else {
yading@10:         int nb_channels = av_get_channel_layout_nb_channels(link->channel_layout);
yading@10: 
yading@10:         if (!s->out) {
yading@10:             s->out = ff_get_audio_buffer(link, link->request_samples);
yading@10:             if (!s->out)
yading@10:                 return AVERROR(ENOMEM);
yading@10: 
yading@10:             s->out->nb_samples = 0;
yading@10:             s->out->pts                   = head->pts;
yading@10:             s->allocated_samples          = link->request_samples;
yading@10:         } else if (link->request_samples != s->allocated_samples) {
yading@10:             av_log(ctx, AV_LOG_ERROR, "request_samples changed before the "
yading@10:                    "buffer was returned.\n");
yading@10:             return AVERROR(EINVAL);
yading@10:         }
yading@10: 
yading@10:         while (s->out->nb_samples < s->allocated_samples) {
yading@10:             int len = FFMIN(s->allocated_samples - s->out->nb_samples,
yading@10:                             head->nb_samples);
yading@10: 
yading@10:             av_samples_copy(s->out->extended_data, head->extended_data,
yading@10:                             s->out->nb_samples, 0, len, nb_channels,
yading@10:                             link->format);
yading@10:             s->out->nb_samples += len;
yading@10: 
yading@10:             if (len == head->nb_samples) {
yading@10:                 av_frame_free(&head);
yading@10:                 queue_pop(s);
yading@10: 
yading@10:                 if (!s->root.next &&
yading@10:                     (ret = ff_request_frame(ctx->inputs[0])) < 0) {
yading@10:                     if (ret == AVERROR_EOF) {
yading@10:                         av_samples_set_silence(s->out->extended_data,
yading@10:                                                s->out->nb_samples,
yading@10:                                                s->allocated_samples -
yading@10:                                                s->out->nb_samples,
yading@10:                                                nb_channels, link->format);
yading@10:                         s->out->nb_samples = s->allocated_samples;
yading@10:                         break;
yading@10:                     }
yading@10:                     return ret;
yading@10:                 }
yading@10:                 head = s->root.next->frame;
yading@10:             } else {
yading@10:                 buffer_offset(link, head, len);
yading@10:             }
yading@10:         }
yading@10:         out = s->out;
yading@10:         s->out = NULL;
yading@10:     }
yading@10:     return ff_filter_frame(link, out);
yading@10: }
yading@10: 
yading@10: static int request_frame(AVFilterLink *outlink)
yading@10: {
yading@10:     FifoContext *fifo = outlink->src->priv;
yading@10:     int ret = 0;
yading@10: 
yading@10:     if (!fifo->root.next) {
yading@10:         if ((ret = ff_request_frame(outlink->src->inputs[0])) < 0)
yading@10:             return ret;
yading@10:         av_assert0(fifo->root.next);
yading@10:     }
yading@10: 
yading@10:     if (outlink->request_samples) {
yading@10:         return return_audio_frame(outlink->src);
yading@10:     } else {
yading@10:         ret = ff_filter_frame(outlink, fifo->root.next->frame);
yading@10:         queue_pop(fifo);
yading@10:     }
yading@10: 
yading@10:     return ret;
yading@10: }
yading@10: 
yading@10: static const AVFilterPad avfilter_vf_fifo_inputs[] = {
yading@10:     {
yading@10:         .name             = "default",
yading@10:         .type             = AVMEDIA_TYPE_VIDEO,
yading@10:         .get_video_buffer = ff_null_get_video_buffer,
yading@10:         .filter_frame     = add_to_queue,
yading@10:     },
yading@10:     { NULL }
yading@10: };
yading@10: 
yading@10: static const AVFilterPad avfilter_vf_fifo_outputs[] = {
yading@10:     {
yading@10:         .name          = "default",
yading@10:         .type          = AVMEDIA_TYPE_VIDEO,
yading@10:         .request_frame = request_frame,
yading@10:     },
yading@10:     { NULL }
yading@10: };
yading@10: 
yading@10: AVFilter avfilter_vf_fifo = {
yading@10:     .name      = "fifo",
yading@10:     .description = NULL_IF_CONFIG_SMALL("Buffer input images and send them when they are requested."),
yading@10: 
yading@10:     .init      = init,
yading@10:     .uninit    = uninit,
yading@10: 
yading@10:     .priv_size = sizeof(FifoContext),
yading@10: 
yading@10:     .inputs    = avfilter_vf_fifo_inputs,
yading@10:     .outputs   = avfilter_vf_fifo_outputs,
yading@10: };
yading@10: 
yading@10: static const AVFilterPad avfilter_af_afifo_inputs[] = {
yading@10:     {
yading@10:         .name             = "default",
yading@10:         .type             = AVMEDIA_TYPE_AUDIO,
yading@10:         .get_audio_buffer = ff_null_get_audio_buffer,
yading@10:         .filter_frame     = add_to_queue,
yading@10:     },
yading@10:     { NULL }
yading@10: };
yading@10: 
yading@10: static const AVFilterPad avfilter_af_afifo_outputs[] = {
yading@10:     {
yading@10:         .name          = "default",
yading@10:         .type          = AVMEDIA_TYPE_AUDIO,
yading@10:         .request_frame = request_frame,
yading@10:     },
yading@10:     { NULL }
yading@10: };
yading@10: 
yading@10: AVFilter avfilter_af_afifo = {
yading@10:     .name        = "afifo",
yading@10:     .description = NULL_IF_CONFIG_SMALL("Buffer input frames and send them when they are requested."),
yading@10: 
yading@10:     .init      = init,
yading@10:     .uninit    = uninit,
yading@10: 
yading@10:     .priv_size = sizeof(FifoContext),
yading@10: 
yading@10:     .inputs    = avfilter_af_afifo_inputs,
yading@10:     .outputs   = avfilter_af_afifo_outputs,
yading@10: };