/*

  * filter layer

  * 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 "libavutil/atomic.h"

 #include "libavutil/avassert.h"
 #include "libavutil/avstring.h"

 #include "libavutil/channel_layout.h"

 #include "libavutil/common.h"

 #include "libavutil/eval.h"

 #include "libavutil/imgutils.h"

 #include "libavutil/internal.h"

 #include "libavutil/opt.h"

 #include "libavutil/pixdesc.h"

 #include "libavutil/rational.h"

 #include "libavutil/samplefmt.h"

 #include "audio.h"

 #include "avfilter.h"

 #include "formats.h"

 #include "internal.h"

 static int ff_filter_frame_framed(AVFilterLink *link, AVFrame *frame);

 void ff_tlog_ref(void *ctx, AVFrame *ref, int end)

 {
     av_unused char buf[16];

     ff_tlog(ctx,

             "ref[%p buf:%p data:%p linesize[%d, %d, %d, %d] pts:%"PRId64" pos:%"PRId64,
             ref, ref->buf, ref->data[0],

             ref->linesize[0], ref->linesize[1], ref->linesize[2], ref->linesize[3],

             ref->pts, av_frame_get_pkt_pos(ref));

     if (ref->width) {

         ff_tlog(ctx, " a:%d/%d s:%dx%d i:%c iskey:%d type:%c",

                 ref->sample_aspect_ratio.num, ref->sample_aspect_ratio.den,
                 ref->width, ref->height,
                 !ref->interlaced_frame     ? 'P' :         /* Progressive  */
                 ref->top_field_first ? 'T' : 'B',    /* Top / Bottom */
                 ref->key_frame,
                 av_get_picture_type_char(ref->pict_type));

     }

     if (ref->nb_samples) {

         ff_tlog(ctx, " cl:%"PRId64"d n:%d r:%d",

                 ref->channel_layout,
                 ref->nb_samples,
                 ref->sample_rate);

     }
 

     ff_tlog(ctx, "]%s", end ? "\n" : "");

 }
 

 unsigned avfilter_version(void)
 {

     av_assert0(LIBAVFILTER_VERSION_MICRO >= 100);

     return LIBAVFILTER_VERSION_INT;
 }
 

 const char *avfilter_configuration(void)

 {

     return FFMPEG_CONFIGURATION;

 }
 

 const char *avfilter_license(void)

 {
 #define LICENSE_PREFIX "libavfilter license: "

     return LICENSE_PREFIX FFMPEG_LICENSE + sizeof(LICENSE_PREFIX) - 1;

 }
 

 void ff_command_queue_pop(AVFilterContext *filter)

 {
     AVFilterCommand *c= filter->command_queue;
     av_freep(&c->arg);
     av_freep(&c->command);
     filter->command_queue= c->next;
     av_free(c);
 }
 

 int ff_insert_pad(unsigned idx, unsigned *count, size_t padidx_off,

                    AVFilterPad **pads, AVFilterLink ***links,
                    AVFilterPad *newpad)

 {

     AVFilterLink **newlinks;
     AVFilterPad *newpads;

     unsigned i;
 
     idx = FFMIN(idx, *count);
 

     newpads  = av_realloc_array(*pads,  *count + 1, sizeof(AVFilterPad));
     newlinks = av_realloc_array(*links, *count + 1, sizeof(AVFilterLink*));
     if (newpads)
         *pads  = newpads;
     if (newlinks)
         *links = newlinks;
     if (!newpads || !newlinks)
         return AVERROR(ENOMEM);
 

     memmove(*pads  + idx + 1, *pads  + idx, sizeof(AVFilterPad)   * (*count - idx));
     memmove(*links + idx + 1, *links + idx, sizeof(AVFilterLink*) * (*count - idx));
     memcpy(*pads + idx, newpad, sizeof(AVFilterPad));

     (*links)[idx] = NULL;
 

     (*count)++;

     for (i = idx + 1; i < *count; i++)

         if ((*links)[i])
             (*(unsigned *)((uint8_t *) (*links)[i] + padidx_off))++;

 
     return 0;

 }
 

 int avfilter_link(AVFilterContext *src, unsigned srcpad,
                   AVFilterContext *dst, unsigned dstpad)
 {
     AVFilterLink *link;
 

     if (src->nb_outputs <= srcpad || dst->nb_inputs <= dstpad ||
         src->outputs[srcpad]      || dst->inputs[dstpad])

         return -1;
 

     if (src->output_pads[srcpad].type != dst->input_pads[dstpad].type) {
         av_log(src, AV_LOG_ERROR,

                "Media type mismatch between the '%s' filter output pad %d (%s) and the '%s' filter input pad %d (%s)\n",
                src->name, srcpad, (char *)av_x_if_null(av_get_media_type_string(src->output_pads[srcpad].type), "?"),
                dst->name, dstpad, (char *)av_x_if_null(av_get_media_type_string(dst-> input_pads[dstpad].type), "?"));

         return AVERROR(EINVAL);
     }
 

     link = av_mallocz(sizeof(*link));
     if (!link)
         return AVERROR(ENOMEM);
 
     src->outputs[srcpad] = dst->inputs[dstpad] = link;

     link->src     = src;
     link->dst     = dst;

     link->srcpad  = &src->output_pads[srcpad];
     link->dstpad  = &dst->input_pads[dstpad];

     link->type    = src->output_pads[srcpad].type;

     av_assert0(AV_PIX_FMT_NONE == -1 && AV_SAMPLE_FMT_NONE == -1);

     link->format  = -1;

 
     return 0;
 }
 

 void avfilter_link_free(AVFilterLink **link)
 {
     if (!*link)
         return;
 

     av_frame_free(&(*link)->partial_buf);

     av_freep(link);
 }
 

 int avfilter_link_get_channels(AVFilterLink *link)
 {
     return link->channels;
 }
 

 void avfilter_link_set_closed(AVFilterLink *link, int closed)
 {
     link->closed = closed;
 }
 

 int avfilter_insert_filter(AVFilterLink *link, AVFilterContext *filt,

                            unsigned filt_srcpad_idx, unsigned filt_dstpad_idx)

 {

     int ret;

     unsigned dstpad_idx = link->dstpad - link->dst->input_pads;
 

     av_log(link->dst, AV_LOG_VERBOSE, "auto-inserting filter '%s' "

            "between the filter '%s' and the filter '%s'\n",
            filt->name, link->src->name, link->dst->name);

     link->dst->inputs[dstpad_idx] = NULL;

     if ((ret = avfilter_link(filt, filt_dstpad_idx, link->dst, dstpad_idx)) < 0) {

         /* failed to link output filter to new filter */

         link->dst->inputs[dstpad_idx] = link;

         return ret;

     }
 
     /* re-hookup the link to the new destination filter we inserted */

     link->dst                     = filt;
     link->dstpad                  = &filt->input_pads[filt_srcpad_idx];

     filt->inputs[filt_srcpad_idx] = link;

     /* if any information on supported media formats already exists on the

      * link, we need to preserve that */

     if (link->out_formats)

         ff_formats_changeref(&link->out_formats,

                              &filt->outputs[filt_dstpad_idx]->out_formats);

     if (link->out_samplerates)

         ff_formats_changeref(&link->out_samplerates,

                              &filt->outputs[filt_dstpad_idx]->out_samplerates);

     if (link->out_channel_layouts)
         ff_channel_layouts_changeref(&link->out_channel_layouts,
                                      &filt->outputs[filt_dstpad_idx]->out_channel_layouts);

     return 0;
 }
 

 int avfilter_config_links(AVFilterContext *filter)

 {
     int (*config_link)(AVFilterLink *);

     unsigned i;

     int ret;

     for (i = 0; i < filter->nb_inputs; i ++) {

         AVFilterLink *link = filter->inputs[i];

         AVFilterLink *inlink;

         if (!link) continue;

         inlink = link->src->nb_inputs ? link->src->inputs[0] : NULL;

         link->current_pts = AV_NOPTS_VALUE;
 

         switch (link->init_state) {

         case AVLINK_INIT:
             continue;
         case AVLINK_STARTINIT:

             av_log(filter, AV_LOG_INFO, "circular filter chain detected\n");
             return 0;

         case AVLINK_UNINIT:
             link->init_state = AVLINK_STARTINIT;
 

             if ((ret = avfilter_config_links(link->src)) < 0)
                 return ret;

             if (!(config_link = link->srcpad->config_props)) {

                 if (link->src->nb_inputs != 1) {

                     av_log(link->src, AV_LOG_ERROR, "Source filters and filters "
                                                     "with more than one input "
                                                     "must set config_props() "
                                                     "callbacks on all outputs\n");
                     return AVERROR(EINVAL);
                 }

             } else if ((ret = config_link(link)) < 0) {
                 av_log(link->src, AV_LOG_ERROR,
                        "Failed to configure output pad on %s\n",
                        link->src->name);

                 return ret;

             }

             switch (link->type) {
             case AVMEDIA_TYPE_VIDEO:
                 if (!link->time_base.num && !link->time_base.den)

                     link->time_base = inlink ? inlink->time_base : AV_TIME_BASE_Q;

 
                 if (!link->sample_aspect_ratio.num && !link->sample_aspect_ratio.den)

                     link->sample_aspect_ratio = inlink ?
                         inlink->sample_aspect_ratio : (AVRational){1,1};

                 if (inlink && !link->frame_rate.num && !link->frame_rate.den)
                     link->frame_rate = inlink->frame_rate;
 

                 if (inlink) {

                     if (!link->w)

                         link->w = inlink->w;

                     if (!link->h)

                         link->h = inlink->h;

                 } else if (!link->w || !link->h) {
                     av_log(link->src, AV_LOG_ERROR,
                            "Video source filters must set their output link's "
                            "width and height\n");
                     return AVERROR(EINVAL);
                 }
                 break;
 
             case AVMEDIA_TYPE_AUDIO:

                 if (inlink) {

                     if (!link->time_base.num && !link->time_base.den)

                         link->time_base = inlink->time_base;

                 }

 
                 if (!link->time_base.num && !link->time_base.den)
                     link->time_base = (AVRational) {1, link->sample_rate};

             }

             if ((config_link = link->dstpad->config_props))

                 if ((ret = config_link(link)) < 0) {
                     av_log(link->src, AV_LOG_ERROR,
                            "Failed to configure input pad on %s\n",
                            link->dst->name);

                     return ret;

                 }

             link->init_state = AVLINK_INIT;
         }
     }
 

     return 0;
 }
 

 void ff_tlog_link(void *ctx, AVFilterLink *link, int end)

 {

     if (link->type == AVMEDIA_TYPE_VIDEO) {

         ff_tlog(ctx,

                 "link[%p s:%dx%d fmt:%s %s->%s]%s",

                 link, link->w, link->h,

                 av_get_pix_fmt_name(link->format),

                 link->src ? link->src->filter->name : "",
                 link->dst ? link->dst->filter->name : "",
                 end ? "\n" : "");

     } else {
         char buf[128];
         av_get_channel_layout_string(buf, sizeof(buf), -1, link->channel_layout);
 

         ff_tlog(ctx,

                 "link[%p r:%d cl:%s fmt:%s %s->%s]%s",

                 link, (int)link->sample_rate, buf,

                 av_get_sample_fmt_name(link->format),
                 link->src ? link->src->filter->name : "",
                 link->dst ? link->dst->filter->name : "",
                 end ? "\n" : "");
     }

 }
 

 int ff_request_frame(AVFilterLink *link)

 {

     int ret = -1;

     FF_TPRINTF_START(NULL, request_frame); ff_tlog_link(NULL, link, 1);

     if (link->closed)
         return AVERROR_EOF;

     av_assert0(!link->frame_requested);
     link->frame_requested = 1;
     while (link->frame_requested) {

         if (link->srcpad->request_frame)
             ret = link->srcpad->request_frame(link);
         else if (link->src->inputs[0])
             ret = ff_request_frame(link->src->inputs[0]);
         if (ret == AVERROR_EOF && link->partial_buf) {
             AVFrame *pbuf = link->partial_buf;
             link->partial_buf = NULL;
             ret = ff_filter_frame_framed(link, pbuf);
         }

         if (ret < 0) {
             link->frame_requested = 0;
             if (ret == AVERROR_EOF)
                 link->closed = 1;
         } else {
             av_assert0(!link->frame_requested ||
                        link->flags & FF_LINK_FLAG_REQUEST_LOOP);
         }
     }

     return ret;

 }
 

 int ff_poll_frame(AVFilterLink *link)

 {

     int i, min = INT_MAX;

     if (link->srcpad->poll_frame)
         return link->srcpad->poll_frame(link);

     for (i = 0; i < link->src->nb_inputs; i++) {

         int val;

         if (!link->src->inputs[i])

             return -1;

         val = ff_poll_frame(link->src->inputs[i]);

         min = FFMIN(min, val);

     }

 
     return min;
 }
 

 static const char *const var_names[] = {   "t",   "n",   "pos",        NULL };
 enum                                   { VAR_T, VAR_N, VAR_POS, VAR_VARS_NB };
 
 static int set_enable_expr(AVFilterContext *ctx, const char *expr)
 {
     int ret;
     char *expr_dup;
     AVExpr *old = ctx->enable;
 
     if (!(ctx->filter->flags & AVFILTER_FLAG_SUPPORT_TIMELINE)) {
         av_log(ctx, AV_LOG_ERROR, "Timeline ('enable' option) not supported "
                "with filter '%s'\n", ctx->filter->name);
         return AVERROR_PATCHWELCOME;
     }
 
     expr_dup = av_strdup(expr);
     if (!expr_dup)
         return AVERROR(ENOMEM);
 
     if (!ctx->var_values) {
         ctx->var_values = av_calloc(VAR_VARS_NB, sizeof(*ctx->var_values));
         if (!ctx->var_values) {
             av_free(expr_dup);
             return AVERROR(ENOMEM);
         }
     }
 
     ret = av_expr_parse((AVExpr**)&ctx->enable, expr_dup, var_names,
                         NULL, NULL, NULL, NULL, 0, ctx->priv);
     if (ret < 0) {
         av_log(ctx->priv, AV_LOG_ERROR,
                "Error when evaluating the expression '%s' for enable\n",
                expr_dup);
         av_free(expr_dup);
         return ret;
     }
 
     av_expr_free(old);
     av_free(ctx->enable_str);
     ctx->enable_str = expr_dup;
     return 0;
 }
 

 void ff_update_link_current_pts(AVFilterLink *link, int64_t pts)

 {

     if (pts == AV_NOPTS_VALUE)

         return;

     link->current_pts = av_rescale_q(pts, link->time_base, AV_TIME_BASE_Q);
     /* TODO use duration */

     if (link->graph && link->age_index >= 0)
         ff_avfilter_graph_update_heap(link->graph, link);
 }
 

 int avfilter_process_command(AVFilterContext *filter, const char *cmd, const char *arg, char *res, int res_len, int flags)
 {
     if(!strcmp(cmd, "ping")){

         char local_res[256] = {0};
 
         if (!res) {
             res = local_res;
             res_len = sizeof(local_res);
         }

         av_strlcatf(res, res_len, "pong from:%s %s\n", filter->filter->name, filter->name);

         if (res == local_res)
             av_log(filter, AV_LOG_INFO, "%s", res);

         return 0;

     }else if(!strcmp(cmd, "enable")) {
         return set_enable_expr(filter, arg);

     }else if(filter->filter->process_command) {
         return filter->filter->process_command(filter, cmd, arg, res, res_len, flags);
     }
     return AVERROR(ENOSYS);
 }
 

 static AVFilter *first_filter;

 static AVFilter **last_filter = &first_filter;

 #if !FF_API_NOCONST_GET_NAME
 const
 #endif

 AVFilter *avfilter_get_by_name(const char *name)

 {

     const AVFilter *f = NULL;

     if (!name)
         return NULL;
 

     while ((f = avfilter_next(f)))
         if (!strcmp(f->name, name))

             return (AVFilter *)f;

 
     return NULL;
 }
 

 int avfilter_register(AVFilter *filter)

 {

     AVFilter **f = last_filter;

     int i;
 

     /* the filter must select generic or internal exclusively */
     av_assert0((filter->flags & AVFILTER_FLAG_SUPPORT_TIMELINE) != AVFILTER_FLAG_SUPPORT_TIMELINE);
 

     for(i=0; filter->inputs && filter->inputs[i].name; i++) {
         const AVFilterPad *input = &filter->inputs[i];
         av_assert0(     !input->filter_frame

                     || (!input->start_frame && !input->end_frame));

     }
 

     filter->next = NULL;

     while(*f || avpriv_atomic_ptr_cas((void * volatile *)f, NULL, filter))

         f = &(*f)->next;

     last_filter = &filter->next;

     return 0;

 }
 

 const AVFilter *avfilter_next(const AVFilter *prev)
 {
     return prev ? prev->next : first_filter;
 }
 
 #if FF_API_OLD_FILTER_REGISTER

 AVFilter **av_filter_next(AVFilter **filter)
 {

     return filter ? &(*filter)->next : &first_filter;

 }
 

 void avfilter_uninit(void)
 {
 }

 #endif

 int avfilter_pad_count(const AVFilterPad *pads)

 {
     int count;
 

     if (!pads)
         return 0;
 

     for (count = 0; pads->name; count++)
         pads++;

     return count;
 }
 

 static const char *default_filter_name(void *filter_ctx)

 {

     AVFilterContext *ctx = filter_ctx;
     return ctx->name ? ctx->name : ctx->filter->name;

 }
 

 static void *filter_child_next(void *obj, void *prev)
 {
     AVFilterContext *ctx = obj;

     if (!prev && ctx->filter && ctx->filter->priv_class && ctx->priv)

         return ctx->priv;
     return NULL;
 }
 
 static const AVClass *filter_child_class_next(const AVClass *prev)
 {

     const AVFilter *f = NULL;

 
     /* find the filter that corresponds to prev */

     while (prev && (f = avfilter_next(f)))
         if (f->priv_class == prev)

             break;
 
     /* could not find filter corresponding to prev */

     if (prev && !f)

         return NULL;
 
     /* find next filter with specific options */

     while ((f = avfilter_next(f)))
         if (f->priv_class)
             return f->priv_class;

     return NULL;
 }
 

 #define OFFSET(x) offsetof(AVFilterContext, x)
 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM

 static const AVOption avfilter_options[] = {

     { "thread_type", "Allowed thread types", OFFSET(thread_type), AV_OPT_TYPE_FLAGS,
         { .i64 = AVFILTER_THREAD_SLICE }, 0, INT_MAX, FLAGS, "thread_type" },
         { "slice", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AVFILTER_THREAD_SLICE }, .unit = "thread_type" },

     { "enable", "set enable expression", OFFSET(enable_str), AV_OPT_TYPE_STRING, {.str=NULL}, .flags = FLAGS },

     { NULL },

 };
 

 static const AVClass avfilter_class = {

     .class_name = "AVFilter",

     .item_name  = default_filter_name,

     .version    = LIBAVUTIL_VERSION_INT,

     .category   = AV_CLASS_CATEGORY_FILTER,

     .child_next = filter_child_next,
     .child_class_next = filter_child_class_next,

     .option           = avfilter_options,

 };
 

 static int default_execute(AVFilterContext *ctx, avfilter_action_func *func, void *arg,

                            int *ret, int nb_jobs)
 {
     int i;
 
     for (i = 0; i < nb_jobs; i++) {
         int r = func(ctx, arg, i, nb_jobs);
         if (ret)
             ret[i] = r;
     }
     return 0;
 }
 

 AVFilterContext *ff_filter_alloc(const AVFilter *filter, const char *inst_name)

 {

     AVFilterContext *ret;
 
     if (!filter)

         return NULL;

     ret = av_mallocz(sizeof(AVFilterContext));

     if (!ret)

         return NULL;

     ret->av_class = &avfilter_class;

     ret->filter   = filter;

     ret->name     = inst_name ? av_strdup(inst_name) : NULL;

     if (filter->priv_size) {

         ret->priv     = av_mallocz(filter->priv_size);

         if (!ret->priv)
             goto err;
     }

     av_opt_set_defaults(ret);

     if (filter->priv_class) {
         *(const AVClass**)ret->priv = filter->priv_class;
         av_opt_set_defaults(ret->priv);
     }
 

     ret->internal = av_mallocz(sizeof(*ret->internal));
     if (!ret->internal)
         goto err;
     ret->internal->execute = default_execute;
 

     ret->nb_inputs = avfilter_pad_count(filter->inputs);

     if (ret->nb_inputs ) {
         ret->input_pads   = av_malloc(sizeof(AVFilterPad) * ret->nb_inputs);

         if (!ret->input_pads)
             goto err;

         memcpy(ret->input_pads, filter->inputs, sizeof(AVFilterPad) * ret->nb_inputs);
         ret->inputs       = av_mallocz(sizeof(AVFilterLink*) * ret->nb_inputs);

         if (!ret->inputs)
             goto err;

     }

     ret->nb_outputs = avfilter_pad_count(filter->outputs);

     if (ret->nb_outputs) {
         ret->output_pads  = av_malloc(sizeof(AVFilterPad) * ret->nb_outputs);

         if (!ret->output_pads)
             goto err;

         memcpy(ret->output_pads, filter->outputs, sizeof(AVFilterPad) * ret->nb_outputs);
         ret->outputs      = av_mallocz(sizeof(AVFilterLink*) * ret->nb_outputs);

         if (!ret->outputs)
             goto err;

     }

 #if FF_API_FOO_COUNT

 FF_DISABLE_DEPRECATION_WARNINGS

     ret->output_count = ret->nb_outputs;
     ret->input_count  = ret->nb_inputs;

 FF_ENABLE_DEPRECATION_WARNINGS

 #endif

     return ret;

 
 err:
     av_freep(&ret->inputs);
     av_freep(&ret->input_pads);

     ret->nb_inputs = 0;

     av_freep(&ret->outputs);
     av_freep(&ret->output_pads);

     ret->nb_outputs = 0;

     av_freep(&ret->priv);

     av_freep(&ret->internal);

     av_free(ret);

     return NULL;

 }
 

 #if FF_API_AVFILTER_OPEN
 int avfilter_open(AVFilterContext **filter_ctx, AVFilter *filter, const char *inst_name)
 {
     *filter_ctx = ff_filter_alloc(filter, inst_name);
     return *filter_ctx ? 0 : AVERROR(ENOMEM);

 }

 #endif

 static void free_link(AVFilterLink *link)
 {
     if (!link)
         return;
 
     if (link->src)
         link->src->outputs[link->srcpad - link->src->output_pads] = NULL;
     if (link->dst)
         link->dst->inputs[link->dstpad - link->dst->input_pads] = NULL;
 
     ff_formats_unref(&link->in_formats);
     ff_formats_unref(&link->out_formats);
     ff_formats_unref(&link->in_samplerates);
     ff_formats_unref(&link->out_samplerates);
     ff_channel_layouts_unref(&link->in_channel_layouts);
     ff_channel_layouts_unref(&link->out_channel_layouts);

     avfilter_link_free(&link);

 }
 

 void avfilter_free(AVFilterContext *filter)

 {
     int i;
 

     if (!filter)
         return;
 

     if (filter->graph)
         ff_filter_graph_remove_filter(filter->graph, filter);
 

     if (filter->filter->uninit)

         filter->filter->uninit(filter);
 

     for (i = 0; i < filter->nb_inputs; i++) {

         free_link(filter->inputs[i]);

     }

     for (i = 0; i < filter->nb_outputs; i++) {

         free_link(filter->outputs[i]);

     }
 

     if (filter->filter->priv_class)

         av_opt_free(filter->priv);
 

     av_freep(&filter->name);
     av_freep(&filter->input_pads);
     av_freep(&filter->output_pads);
     av_freep(&filter->inputs);
     av_freep(&filter->outputs);
     av_freep(&filter->priv);

     while(filter->command_queue){

         ff_command_queue_pop(filter);

     }

     av_opt_free(filter);
     av_expr_free(filter->enable);
     filter->enable = NULL;
     av_freep(&filter->var_values);

     av_freep(&filter->internal);

     av_free(filter);
 }
 

 static int process_options(AVFilterContext *ctx, AVDictionary **options,
                            const char *args)

 {
     const AVOption *o = NULL;

     int ret, count = 0;
     char *av_uninit(parsed_key), *av_uninit(value);
     const char *key;

     int offset= -1;

     if (!args)
         return 0;
 
     while (*args) {
         const char *shorthand = NULL;
 

         o = av_opt_next(ctx->priv, o);

         if (o) {
             if (o->type == AV_OPT_TYPE_CONST || o->offset == offset)
                 continue;
             offset = o->offset;
             shorthand = o->name;

         }
 

         ret = av_opt_get_key_value(&args, "=", ":",
                                    shorthand ? AV_OPT_FLAG_IMPLICIT_KEY : 0,
                                    &parsed_key, &value);
         if (ret < 0) {
             if (ret == AVERROR(EINVAL))
                 av_log(ctx, AV_LOG_ERROR, "No option name near '%s'\n", args);
             else
                 av_log(ctx, AV_LOG_ERROR, "Unable to parse '%s': %s\n", args,
                        av_err2str(ret));
             return ret;
         }
         if (*args)
             args++;
         if (parsed_key) {
             key = parsed_key;
             while ((o = av_opt_next(ctx->priv, o))); /* discard all remaining shorthand */
         } else {
             key = shorthand;
         }

         av_log(ctx, AV_LOG_DEBUG, "Setting '%s' to value '%s'\n", key, value);

 
         if (av_opt_find(ctx, key, NULL, 0, 0)) {
             ret = av_opt_set(ctx, key, value, 0);

             if (ret < 0) {
                 av_free(value);
                 av_free(parsed_key);

                 return ret;

             }

         } else {

         av_dict_set(options, key, value, 0);
         if ((ret = av_opt_set(ctx->priv, key, value, 0)) < 0) {

             if (!av_opt_find(ctx->priv, key, NULL, 0, AV_OPT_SEARCH_CHILDREN | AV_OPT_SEARCH_FAKE_OBJ)) {

             if (ret == AVERROR_OPTION_NOT_FOUND)
                 av_log(ctx, AV_LOG_ERROR, "Option '%s' not found\n", key);
             av_free(value);
             av_free(parsed_key);
             return ret;

             }

         }

         }

         av_free(value);
         av_free(parsed_key);
         count++;

     }

 
     if (ctx->enable_str) {

         ret = set_enable_expr(ctx, ctx->enable_str);

         if (ret < 0)
             return ret;
     }

     return count;

 }
 

 #if FF_API_AVFILTER_INIT_FILTER

 int avfilter_init_filter(AVFilterContext *filter, const char *args, void *opaque)

 {

     return avfilter_init_str(filter, args);
 }
 #endif
 

 int avfilter_init_dict(AVFilterContext *ctx, AVDictionary **options)
 {
     int ret = 0;
 

     ret = av_opt_set_dict(ctx, options);
     if (ret < 0) {
         av_log(ctx, AV_LOG_ERROR, "Error applying generic filter options.\n");
         return ret;
     }
 
     if (ctx->filter->flags & AVFILTER_FLAG_SLICE_THREADS &&
         ctx->thread_type & ctx->graph->thread_type & AVFILTER_THREAD_SLICE &&
         ctx->graph->internal->thread_execute) {
         ctx->thread_type       = AVFILTER_THREAD_SLICE;
         ctx->internal->execute = ctx->graph->internal->thread_execute;
     } else {
         ctx->thread_type = 0;
     }
 

     if (ctx->filter->priv_class) {
         ret = av_opt_set_dict(ctx->priv, options);
         if (ret < 0) {
             av_log(ctx, AV_LOG_ERROR, "Error applying options to the filter.\n");
             return ret;
         }
     }
 

     if (ctx->filter->init_opaque)
         ret = ctx->filter->init_opaque(ctx, NULL);
     else if (ctx->filter->init)

         ret = ctx->filter->init(ctx);
     else if (ctx->filter->init_dict)
         ret = ctx->filter->init_dict(ctx, options);
 
     return ret;
 }
 

 int avfilter_init_str(AVFilterContext *filter, const char *args)

 {

     AVDictionary *options = NULL;
     AVDictionaryEntry *e;

     int ret = 0;

     if (args && *args) {

         if (!filter->filter->priv_class) {
             av_log(filter, AV_LOG_ERROR, "This filter does not take any "
                    "options, but options were provided: %s.\n", args);
             return AVERROR(EINVAL);
         }
 

 #if FF_API_OLD_FILTER_OPTS

             if (   !strcmp(filter->filter->name, "format")     ||

                    !strcmp(filter->filter->name, "noformat")   ||
                    !strcmp(filter->filter->name, "frei0r")     ||

                    !strcmp(filter->filter->name, "frei0r_src") ||

                    !strcmp(filter->filter->name, "ocv")        ||

                    !strcmp(filter->filter->name, "pan")        ||

                    !strcmp(filter->filter->name, "pp")         ||
                    !strcmp(filter->filter->name, "aevalsrc")) {

             /* a hack for compatibility with the old syntax
              * replace colons with |s */
             char *copy = av_strdup(args);
             char *p    = copy;

             int nb_leading = 0; // number of leading colons to skip

             int deprecated = 0;

 
             if (!copy) {
                 ret = AVERROR(ENOMEM);
                 goto fail;
             }
 

             if (!strcmp(filter->filter->name, "frei0r") ||
                 !strcmp(filter->filter->name, "ocv"))

                 nb_leading = 1;
             else if (!strcmp(filter->filter->name, "frei0r_src"))
                 nb_leading = 3;
 
             while (nb_leading--) {
                 p = strchr(p, ':');
                 if (!p) {
                     p = copy + strlen(copy);
                     break;
                 }
                 p++;
             }
 

             deprecated = strchr(p, ':') != NULL;

             if (!strcmp(filter->filter->name, "aevalsrc")) {

                 deprecated = 0;

                 while ((p = strchr(p, ':')) && p[1] != ':') {
                     const char *epos = strchr(p + 1, '=');
                     const char *spos = strchr(p + 1, ':');
                     const int next_token_is_opt = epos && (!spos || epos < spos);
                     if (next_token_is_opt) {
                         p++;
                         break;
                     }

                     /* next token does not contain a '=', assume a channel expression */
                     deprecated = 1;

                     *p++ = '|';
                 }

                 if (p && *p == ':') { // double sep '::' found
                     deprecated = 1;

                     memmove(p, p + 1, strlen(p));

                 }

             } else

             while ((p = strchr(p, ':')))
                 *p++ = '|';
 

             if (deprecated)
                 av_log(filter, AV_LOG_WARNING, "This syntax is deprecated. Use "
                        "'|' to separate the list items.\n");
 

             av_log(filter, AV_LOG_DEBUG, "compat: called with args=[%s]\n", copy);

             ret = process_options(filter, &options, copy);

             av_freep(&copy);
 
             if (ret < 0)
                 goto fail;
 #endif

         } else {

 #if CONFIG_MP_FILTER
             if (!strcmp(filter->filter->name, "mp")) {
                 char *escaped;
 
                 if (!strncmp(args, "filter=", 7))
                     args += 7;
                 ret = av_escape(&escaped, args, ":=", AV_ESCAPE_MODE_BACKSLASH, 0);
                 if (ret < 0) {
                     av_log(filter, AV_LOG_ERROR, "Unable to escape MPlayer filters arg '%s'\n", args);
                     goto fail;
                 }
                 ret = process_options(filter, &options, escaped);
                 av_free(escaped);
             } else
 #endif

             ret = process_options(filter, &options, args);

             if (ret < 0)
                 goto fail;
         }
     }
 

     ret = avfilter_init_dict(filter, &options);

     if (ret < 0)
         goto fail;

 
     if ((e = av_dict_get(options, "", NULL, AV_DICT_IGNORE_SUFFIX))) {
         av_log(filter, AV_LOG_ERROR, "No such option: %s.\n", e->key);
         ret = AVERROR_OPTION_NOT_FOUND;
         goto fail;
     }
 
 fail:
     av_dict_free(&options);
 

     return ret;

 }

 const char *avfilter_pad_get_name(const AVFilterPad *pads, int pad_idx)

 {
     return pads[pad_idx].name;
 }
 

 enum AVMediaType avfilter_pad_get_type(const AVFilterPad *pads, int pad_idx)

 {
     return pads[pad_idx].type;

 }

 static int default_filter_frame(AVFilterLink *link, AVFrame *frame)

 {
     return ff_filter_frame(link->dst->outputs[0], frame);
 }
 

 static int ff_filter_frame_framed(AVFilterLink *link, AVFrame *frame)

 {

     int (*filter_frame)(AVFilterLink *, AVFrame *);

     AVFilterContext *dstctx = link->dst;

     AVFilterPad *dst = link->dstpad;

     AVFrame *out = NULL;

     int ret;

     AVFilterCommand *cmd= link->dst->command_queue;
     int64_t pts;
 
     if (link->closed) {

         av_frame_free(&frame);

         return AVERROR_EOF;
     }
 
     if (!(filter_frame = dst->filter_frame))
         filter_frame = default_filter_frame;
 

     /* copy the frame if needed */
     if (dst->needs_writable && !av_frame_is_writable(frame)) {
         av_log(link->dst, AV_LOG_DEBUG, "Copying data in avfilter.\n");

 
         /* Maybe use ff_copy_buffer_ref instead? */
         switch (link->type) {
         case AVMEDIA_TYPE_VIDEO:

             out = ff_get_video_buffer(link, link->w, link->h);

             break;
         case AVMEDIA_TYPE_AUDIO:

             out = ff_get_audio_buffer(link, frame->nb_samples);

             break;

         default:
             ret = AVERROR(EINVAL);
             goto fail;

         }
         if (!out) {

             ret = AVERROR(ENOMEM);
             goto fail;

         }

 
         ret = av_frame_copy_props(out, frame);
         if (ret < 0)
             goto fail;

 
         switch (link->type) {
         case AVMEDIA_TYPE_VIDEO:

             av_image_copy(out->data, out->linesize, (const uint8_t **)frame->data, frame->linesize,

                           frame->format, frame->width, frame->height);

             break;
         case AVMEDIA_TYPE_AUDIO:
             av_samples_copy(out->extended_data, frame->extended_data,

                             0, 0, frame->nb_samples,
                             av_get_channel_layout_nb_channels(frame->channel_layout),

                             frame->format);
             break;

         default:
             ret = AVERROR(EINVAL);
             goto fail;

         }
 

         av_frame_free(&frame);

     } else
         out = frame;
 

     while(cmd && cmd->time <= out->pts * av_q2d(link->time_base)){

         av_log(link->dst, AV_LOG_DEBUG,
                "Processing command time:%f command:%s arg:%s\n",
                cmd->time, cmd->command, cmd->arg);
         avfilter_process_command(link->dst, cmd->command, cmd->arg, 0, 0, cmd->flags);
         ff_command_queue_pop(link->dst);
         cmd= link->dst->command_queue;
     }
 
     pts = out->pts;

     if (dstctx->enable_str) {
         int64_t pos = av_frame_get_pkt_pos(out);
         dstctx->var_values[VAR_N] = link->frame_count;
         dstctx->var_values[VAR_T] = pts == AV_NOPTS_VALUE ? NAN : pts * av_q2d(link->time_base);
         dstctx->var_values[VAR_POS] = pos == -1 ? NAN : pos;

         dstctx->is_disabled = fabs(av_expr_eval(dstctx->enable, dstctx->var_values, NULL)) < 0.5;

         if (dstctx->is_disabled &&
             (dstctx->filter->flags & AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC))
             filter_frame = default_filter_frame;

     }

     ret = filter_frame(link, out);

     link->frame_count++;

     link->frame_requested = 0;

     ff_update_link_current_pts(link, pts);
     return ret;

 
 fail:
     av_frame_free(&out);
     av_frame_free(&frame);
     return ret;

 }
 

 static int ff_filter_frame_needs_framing(AVFilterLink *link, AVFrame *frame)

 {

     int insamples = frame->nb_samples, inpos = 0, nb_samples;
     AVFrame *pbuf = link->partial_buf;

     int nb_channels = av_frame_get_channels(frame);

     int ret = 0;
 

     link->flags |= FF_LINK_FLAG_REQUEST_LOOP;

     /* Handle framing (min_samples, max_samples) */
     while (insamples) {
         if (!pbuf) {
             AVRational samples_tb = { 1, link->sample_rate };

             pbuf = ff_get_audio_buffer(link, link->partial_buf_size);

             if (!pbuf) {
                 av_log(link->dst, AV_LOG_WARNING,
                        "Samples dropped due to memory allocation failure.\n");
                 return 0;
             }

             av_frame_copy_props(pbuf, frame);

             pbuf->pts = frame->pts;
             if (pbuf->pts != AV_NOPTS_VALUE)
                 pbuf->pts += av_rescale_q(inpos, samples_tb, link->time_base);

             pbuf->nb_samples = 0;

         }
         nb_samples = FFMIN(insamples,

                            link->partial_buf_size - pbuf->nb_samples);

         av_samples_copy(pbuf->extended_data, frame->extended_data,

                         pbuf->nb_samples, inpos,

                         nb_samples, nb_channels, link->format);
         inpos                   += nb_samples;
         insamples               -= nb_samples;

         pbuf->nb_samples += nb_samples;
         if (pbuf->nb_samples >= link->min_samples) {

             ret = ff_filter_frame_framed(link, pbuf);
             pbuf = NULL;
         }
     }

     av_frame_free(&frame);

     link->partial_buf = pbuf;
     return ret;
 }
 

 int ff_filter_frame(AVFilterLink *link, AVFrame *frame)

 {
     FF_TPRINTF_START(NULL, filter_frame); ff_tlog_link(NULL, link, 1); ff_tlog(NULL, " "); ff_tlog_ref(NULL, frame, 1);
 

     /* Consistency checks */
     if (link->type == AVMEDIA_TYPE_VIDEO) {
         if (strcmp(link->dst->filter->name, "scale")) {
             av_assert1(frame->format                 == link->format);

             av_assert1(frame->width               == link->w);
             av_assert1(frame->height               == link->h);

         }
     } else {
         av_assert1(frame->format                == link->format);

         av_assert1(av_frame_get_channels(frame) == link->channels);

         av_assert1(frame->channel_layout        == link->channel_layout);
         av_assert1(frame->sample_rate           == link->sample_rate);

     }
 
     /* Go directly to actual filtering if possible */
     if (link->type == AVMEDIA_TYPE_AUDIO &&
         link->min_samples &&
         (link->partial_buf ||

          frame->nb_samples < link->min_samples ||
          frame->nb_samples > link->max_samples)) {

         return ff_filter_frame_needs_framing(link, frame);
     } else {
         return ff_filter_frame_framed(link, frame);

     }
 }

 
 const AVClass *avfilter_get_class(void)
 {
     return &avfilter_class;
 }