libavfilter/vsrc_buffer.c
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00001 /*
00002  * Copyright (c) 2008 Vitor Sessak
00003  *
00004  * This file is part of FFmpeg.
00005  *
00006  * FFmpeg is free software; you can redistribute it and/or
00007  * modify it under the terms of the GNU Lesser General Public
00008  * License as published by the Free Software Foundation; either
00009  * version 2.1 of the License, or (at your option) any later version.
00010  *
00011  * FFmpeg is distributed in the hope that it will be useful,
00012  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00013  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00014  * Lesser General Public License for more details.
00015  *
00016  * You should have received a copy of the GNU Lesser General Public
00017  * License along with FFmpeg; if not, write to the Free Software
00018  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00019  */
00020 
00026 #include "avfilter.h"
00027 #include "internal.h"
00028 #include "avcodec.h"
00029 #include "buffersrc.h"
00030 #include "vsrc_buffer.h"
00031 #include "libavutil/imgutils.h"
00032 
00033 typedef struct {
00034     AVFilterBufferRef *picref;
00035     int               h, w;
00036     enum PixelFormat  pix_fmt;
00037     AVRational        time_base;     
00038     AVRational        sample_aspect_ratio;
00039     char              sws_param[256];
00040 } BufferSourceContext;
00041 
00042 #define CHECK_PARAM_CHANGE(s, c, width, height, format)\
00043     if (c->w != width || c->h != height || c->pix_fmt != format) {\
00044         av_log(s, AV_LOG_ERROR, "Changing frame properties on the fly is not supported.\n");\
00045         return AVERROR(EINVAL);\
00046     }
00047 
00048 int av_vsrc_buffer_add_video_buffer_ref(AVFilterContext *buffer_filter,
00049                                         AVFilterBufferRef *picref, int flags)
00050 {
00051     BufferSourceContext *c = buffer_filter->priv;
00052     AVFilterLink *outlink = buffer_filter->outputs[0];
00053     int ret;
00054 
00055     if (c->picref) {
00056         if (flags & AV_VSRC_BUF_FLAG_OVERWRITE) {
00057             avfilter_unref_buffer(c->picref);
00058             c->picref = NULL;
00059         } else {
00060             av_log(buffer_filter, AV_LOG_ERROR,
00061                    "Buffering several frames is not supported. "
00062                    "Please consume all available frames before adding a new one.\n");
00063             return AVERROR(EINVAL);
00064         }
00065     }
00066 
00067     if (picref->video->w != c->w || picref->video->h != c->h || picref->format != c->pix_fmt) {
00068         AVFilterContext *scale = buffer_filter->outputs[0]->dst;
00069         AVFilterLink *link;
00070         char scale_param[1024];
00071 
00072         av_log(buffer_filter, AV_LOG_INFO,
00073                "Buffer video input changed from size:%dx%d fmt:%s to size:%dx%d fmt:%s\n",
00074                c->w, c->h, av_pix_fmt_descriptors[c->pix_fmt].name,
00075                picref->video->w, picref->video->h, av_pix_fmt_descriptors[picref->format].name);
00076 
00077         if (!scale || strcmp(scale->filter->name, "scale")) {
00078             AVFilter *f = avfilter_get_by_name("scale");
00079 
00080             av_log(buffer_filter, AV_LOG_INFO, "Inserting scaler filter\n");
00081             if ((ret = avfilter_open(&scale, f, "Input equalizer")) < 0)
00082                 return ret;
00083 
00084             snprintf(scale_param, sizeof(scale_param)-1, "%d:%d:%s", c->w, c->h, c->sws_param);
00085             if ((ret = avfilter_init_filter(scale, scale_param, NULL)) < 0) {
00086                 avfilter_free(scale);
00087                 return ret;
00088             }
00089 
00090             if ((ret = avfilter_insert_filter(buffer_filter->outputs[0], scale, 0, 0)) < 0) {
00091                 avfilter_free(scale);
00092                 return ret;
00093             }
00094             scale->outputs[0]->time_base = scale->inputs[0]->time_base;
00095 
00096             scale->outputs[0]->format= c->pix_fmt;
00097         } else if (!strcmp(scale->filter->name, "scale")) {
00098             snprintf(scale_param, sizeof(scale_param)-1, "%d:%d:%s",
00099                      scale->outputs[0]->w, scale->outputs[0]->h, c->sws_param);
00100             scale->filter->init(scale, scale_param, NULL);
00101         }
00102 
00103         c->pix_fmt = scale->inputs[0]->format = picref->format;
00104         c->w       = scale->inputs[0]->w      = picref->video->w;
00105         c->h       = scale->inputs[0]->h      = picref->video->h;
00106 
00107         link = scale->outputs[0];
00108         if ((ret =  link->srcpad->config_props(link)) < 0)
00109             return ret;
00110     }
00111 
00112     c->picref = avfilter_get_video_buffer(outlink, AV_PERM_WRITE,
00113                                           picref->video->w, picref->video->h);
00114     av_image_copy(c->picref->data, c->picref->linesize,
00115                   (void*)picref->data, picref->linesize,
00116                   picref->format, picref->video->w, picref->video->h);
00117     avfilter_copy_buffer_ref_props(c->picref, picref);
00118 
00119     return 0;
00120 }
00121 
00122 int av_buffersrc_buffer(AVFilterContext *s, AVFilterBufferRef *buf)
00123 {
00124     BufferSourceContext *c = s->priv;
00125 
00126     if (c->picref) {
00127         av_log(s, AV_LOG_ERROR,
00128                "Buffering several frames is not supported. "
00129                "Please consume all available frames before adding a new one.\n"
00130             );
00131         return AVERROR(EINVAL);
00132     }
00133 
00134 //     CHECK_PARAM_CHANGE(s, c, buf->video->w, buf->video->h, buf->format);
00135 
00136     c->picref = buf;
00137 
00138     return 0;
00139 }
00140 
00141 #if CONFIG_AVCODEC
00142 #include "avcodec.h"
00143 
00144 int av_vsrc_buffer_add_frame(AVFilterContext *buffer_src,
00145                              const AVFrame *frame, int flags)
00146 {
00147     int ret;
00148     AVFilterBufferRef *picref =
00149         avfilter_get_video_buffer_ref_from_frame(frame, AV_PERM_WRITE);
00150     if (!picref)
00151         return AVERROR(ENOMEM);
00152     ret = av_vsrc_buffer_add_video_buffer_ref(buffer_src, picref, flags);
00153     picref->buf->data[0] = NULL;
00154     avfilter_unref_buffer(picref);
00155 
00156     return ret;
00157 }
00158 #endif
00159 
00160 static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
00161 {
00162     BufferSourceContext *c = ctx->priv;
00163     char pix_fmt_str[128];
00164     int ret, n = 0;
00165     *c->sws_param = 0;
00166 
00167     if (!args ||
00168         (n = sscanf(args, "%d:%d:%127[^:]:%d:%d:%d:%d:%255c", &c->w, &c->h, pix_fmt_str,
00169                     &c->time_base.num, &c->time_base.den,
00170                     &c->sample_aspect_ratio.num, &c->sample_aspect_ratio.den, c->sws_param)) < 7) {
00171         av_log(ctx, AV_LOG_ERROR, "Expected at least 7 arguments, but only %d found in '%s'\n", n, args);
00172         return AVERROR(EINVAL);
00173     }
00174 
00175     if ((ret = ff_parse_pixel_format(&c->pix_fmt, pix_fmt_str, ctx)) < 0)
00176         return ret;
00177 
00178     av_log(ctx, AV_LOG_INFO, "w:%d h:%d pixfmt:%s tb:%d/%d sar:%d/%d sws_param:%s\n",
00179            c->w, c->h, av_pix_fmt_descriptors[c->pix_fmt].name,
00180            c->time_base.num, c->time_base.den,
00181            c->sample_aspect_ratio.num, c->sample_aspect_ratio.den, c->sws_param);
00182     return 0;
00183 }
00184 
00185 static av_cold void uninit(AVFilterContext *ctx)
00186 {
00187     BufferSourceContext *s = ctx->priv;
00188     if (s->picref)
00189         avfilter_unref_buffer(s->picref);
00190     s->picref = NULL;
00191 }
00192 
00193 static int query_formats(AVFilterContext *ctx)
00194 {
00195     BufferSourceContext *c = ctx->priv;
00196     enum PixelFormat pix_fmts[] = { c->pix_fmt, PIX_FMT_NONE };
00197 
00198     avfilter_set_common_pixel_formats(ctx, avfilter_make_format_list(pix_fmts));
00199     return 0;
00200 }
00201 
00202 static int config_props(AVFilterLink *link)
00203 {
00204     BufferSourceContext *c = link->src->priv;
00205 
00206     link->w = c->w;
00207     link->h = c->h;
00208     link->sample_aspect_ratio = c->sample_aspect_ratio;
00209     link->time_base = c->time_base;
00210 
00211     return 0;
00212 }
00213 
00214 static int request_frame(AVFilterLink *link)
00215 {
00216     BufferSourceContext *c = link->src->priv;
00217 
00218     if (!c->picref) {
00219         av_log(link->src, AV_LOG_WARNING,
00220                "request_frame() called with no available frame!\n");
00221         return AVERROR(EINVAL);
00222     }
00223 
00224     avfilter_start_frame(link, avfilter_ref_buffer(c->picref, ~0));
00225     avfilter_draw_slice(link, 0, link->h, 1);
00226     avfilter_end_frame(link);
00227     avfilter_unref_buffer(c->picref);
00228     c->picref = NULL;
00229 
00230     return 0;
00231 }
00232 
00233 static int poll_frame(AVFilterLink *link)
00234 {
00235     BufferSourceContext *c = link->src->priv;
00236     return !!c->picref;
00237 }
00238 
00239 AVFilter avfilter_vsrc_buffer = {
00240     .name      = "buffer",
00241     .description = NULL_IF_CONFIG_SMALL("Buffer video frames, and make them accessible to the filterchain."),
00242     .priv_size = sizeof(BufferSourceContext),
00243     .query_formats = query_formats,
00244 
00245     .init      = init,
00246     .uninit    = uninit,
00247 
00248     .inputs    = (const AVFilterPad[]) {{ .name = NULL }},
00249     .outputs   = (const AVFilterPad[]) {{ .name      = "default",
00250                                     .type            = AVMEDIA_TYPE_VIDEO,
00251                                     .request_frame   = request_frame,
00252                                     .poll_frame      = poll_frame,
00253                                     .config_props    = config_props, },
00254                                   { .name = NULL}},
00255 };