/*

  * ffmpeg filter configuration

  *

  * 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 <stdint.h>
 

 #include "ffmpeg.h"

 
 #include "libavfilter/avfilter.h"

 #include "libavfilter/buffersink.h"

 #include "libavfilter/buffersrc.h"

 #include "libavresample/avresample.h"
 

 #include "libavutil/avassert.h"

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

 #include "libavutil/channel_layout.h"

 #include "libavutil/display.h"

 #include "libavutil/opt.h"

 #include "libavutil/pixdesc.h"
 #include "libavutil/pixfmt.h"

 #include "libavutil/imgutils.h"

 #include "libavutil/samplefmt.h"
 

 static const enum AVPixelFormat *get_compliance_unofficial_pix_fmts(enum AVCodecID codec_id, const enum AVPixelFormat default_formats[])
 {
     static const enum AVPixelFormat mjpeg_formats[] =
         { AV_PIX_FMT_YUVJ420P, AV_PIX_FMT_YUVJ422P, AV_PIX_FMT_YUVJ444P,
           AV_PIX_FMT_YUV420P,  AV_PIX_FMT_YUV422P,  AV_PIX_FMT_YUV444P,
           AV_PIX_FMT_NONE };
     static const enum AVPixelFormat ljpeg_formats[] =
         { AV_PIX_FMT_BGR24   , AV_PIX_FMT_BGRA    , AV_PIX_FMT_BGR0,
           AV_PIX_FMT_YUVJ420P, AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_YUVJ422P,
           AV_PIX_FMT_YUV420P , AV_PIX_FMT_YUV444P , AV_PIX_FMT_YUV422P,
           AV_PIX_FMT_NONE};
 
     if (codec_id == AV_CODEC_ID_MJPEG) {
         return mjpeg_formats;
     } else if (codec_id == AV_CODEC_ID_LJPEG) {
         return ljpeg_formats;
     } else {
         return default_formats;
     }
 }
 

 enum AVPixelFormat choose_pixel_fmt(AVStream *st, AVCodecContext *enc_ctx, AVCodec *codec, enum AVPixelFormat target)

 {
     if (codec && codec->pix_fmts) {

         const enum AVPixelFormat *p = codec->pix_fmts;

         const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(target);
         int has_alpha = desc ? desc->nb_components % 2 == 0 : 0;

         enum AVPixelFormat best= AV_PIX_FMT_NONE;

         if (enc_ctx->strict_std_compliance <= FF_COMPLIANCE_UNOFFICIAL) {

             p = get_compliance_unofficial_pix_fmts(enc_ctx->codec_id, p);

         }

         for (; *p != AV_PIX_FMT_NONE; p++) {

             best= avcodec_find_best_pix_fmt_of_2(best, *p, target, has_alpha, NULL);

             if (*p == target)
                 break;
         }

         if (*p == AV_PIX_FMT_NONE) {
             if (target != AV_PIX_FMT_NONE)

                 av_log(NULL, AV_LOG_WARNING,
                        "Incompatible pixel format '%s' for codec '%s', auto-selecting format '%s'\n",

                        av_get_pix_fmt_name(target),

                        codec->name,

                        av_get_pix_fmt_name(best));

             return best;
         }
     }
     return target;
 }
 
 void choose_sample_fmt(AVStream *st, AVCodec *codec)
 {
     if (codec && codec->sample_fmts) {
         const enum AVSampleFormat *p = codec->sample_fmts;
         for (; *p != -1; p++) {

             if (*p == st->codecpar->format)

                 break;
         }
         if (*p == -1) {

             if((codec->capabilities & AV_CODEC_CAP_LOSSLESS) && av_get_sample_fmt_name(st->codecpar->format) > av_get_sample_fmt_name(codec->sample_fmts[0]))

                 av_log(NULL, AV_LOG_ERROR, "Conversion will not be lossless.\n");

             if(av_get_sample_fmt_name(st->codecpar->format))

             av_log(NULL, AV_LOG_WARNING,
                    "Incompatible sample format '%s' for codec '%s', auto-selecting format '%s'\n",

                    av_get_sample_fmt_name(st->codecpar->format),

                    codec->name,
                    av_get_sample_fmt_name(codec->sample_fmts[0]));

             st->codecpar->format = codec->sample_fmts[0];

         }
     }
 }
 
 static char *choose_pix_fmts(OutputStream *ost)
 {

     AVDictionaryEntry *strict_dict = av_dict_get(ost->encoder_opts, "strict", NULL, 0);

     if (strict_dict)
         // used by choose_pixel_fmt() and below

         av_opt_set(ost->enc_ctx, "strict", strict_dict->value, 0);

      if (ost->keep_pix_fmt) {
         if (ost->filter)
             avfilter_graph_set_auto_convert(ost->filter->graph->graph,
                                             AVFILTER_AUTO_CONVERT_NONE);

         if (ost->enc_ctx->pix_fmt == AV_PIX_FMT_NONE)

             return NULL;

         return av_strdup(av_get_pix_fmt_name(ost->enc_ctx->pix_fmt));

     }

     if (ost->enc_ctx->pix_fmt != AV_PIX_FMT_NONE) {

         return av_strdup(av_get_pix_fmt_name(choose_pixel_fmt(ost->st, ost->enc_ctx, ost->enc, ost->enc_ctx->pix_fmt)));

     } else if (ost->enc && ost->enc->pix_fmts) {

         const enum AVPixelFormat *p;

         AVIOContext *s = NULL;
         uint8_t *ret;
         int len;
 
         if (avio_open_dyn_buf(&s) < 0)

             exit_program(1);

 
         p = ost->enc->pix_fmts;

         if (ost->enc_ctx->strict_std_compliance <= FF_COMPLIANCE_UNOFFICIAL) {

             p = get_compliance_unofficial_pix_fmts(ost->enc_ctx->codec_id, p);

         }
 

         for (; *p != AV_PIX_FMT_NONE; p++) {

             const char *name = av_get_pix_fmt_name(*p);

             avio_printf(s, "%s|", name);

         }
         len = avio_close_dyn_buf(s, &ret);
         ret[len - 1] = 0;
         return ret;
     } else
         return NULL;
 }
 

 /* Define a function for building a string containing a list of
  * allowed formats. */

 #define DEF_CHOOSE_FORMAT(type, var, supported_list, none, get_name)           \

 static char *choose_ ## var ## s(OutputStream *ost)                            \
 {                                                                              \

     if (ost->enc_ctx->var != none) {                                           \
         get_name(ost->enc_ctx->var);                                           \

         return av_strdup(name);                                                \

     } else if (ost->enc && ost->enc->supported_list) {                         \

         const type *p;                                                         \
         AVIOContext *s = NULL;                                                 \
         uint8_t *ret;                                                          \
         int len;                                                               \
                                                                                \
         if (avio_open_dyn_buf(&s) < 0)                                         \

             exit_program(1);                                                           \

                                                                                \
         for (p = ost->enc->supported_list; *p != none; p++) {                  \
             get_name(*p);                                                      \

             avio_printf(s, "%s|", name);                                       \

         }                                                                      \
         len = avio_close_dyn_buf(s, &ret);                                     \
         ret[len - 1] = 0;                                                      \
         return ret;                                                            \
     } else                                                                     \
         return NULL;                                                           \
 }
 

 // DEF_CHOOSE_FORMAT(enum AVPixelFormat, pix_fmt, pix_fmts, AV_PIX_FMT_NONE,

 //                   GET_PIX_FMT_NAME)

 
 DEF_CHOOSE_FORMAT(enum AVSampleFormat, sample_fmt, sample_fmts,

                   AV_SAMPLE_FMT_NONE, GET_SAMPLE_FMT_NAME)

 
 DEF_CHOOSE_FORMAT(int, sample_rate, supported_samplerates, 0,

                   GET_SAMPLE_RATE_NAME)

 
 DEF_CHOOSE_FORMAT(uint64_t, channel_layout, channel_layouts, 0,

                   GET_CH_LAYOUT_NAME)

 int init_simple_filtergraph(InputStream *ist, OutputStream *ost)

 {
     FilterGraph *fg = av_mallocz(sizeof(*fg));
 
     if (!fg)

         exit_program(1);

     fg->index = nb_filtergraphs;
 

     GROW_ARRAY(fg->outputs, fg->nb_outputs);

     if (!(fg->outputs[0] = av_mallocz(sizeof(*fg->outputs[0]))))

         exit_program(1);

     fg->outputs[0]->ost   = ost;
     fg->outputs[0]->graph = fg;
 
     ost->filter = fg->outputs[0];
 

     GROW_ARRAY(fg->inputs, fg->nb_inputs);

     if (!(fg->inputs[0] = av_mallocz(sizeof(*fg->inputs[0]))))

         exit_program(1);

     fg->inputs[0]->ist   = ist;
     fg->inputs[0]->graph = fg;
 

     GROW_ARRAY(ist->filters, ist->nb_filters);

     ist->filters[ist->nb_filters - 1] = fg->inputs[0];
 

     GROW_ARRAY(filtergraphs, nb_filtergraphs);

     filtergraphs[nb_filtergraphs - 1] = fg;
 

     return 0;

 }
 
 static void init_input_filter(FilterGraph *fg, AVFilterInOut *in)
 {
     InputStream *ist = NULL;
     enum AVMediaType type = avfilter_pad_get_type(in->filter_ctx->input_pads, in->pad_idx);
     int i;
 
     // TODO: support other filter types
     if (type != AVMEDIA_TYPE_VIDEO && type != AVMEDIA_TYPE_AUDIO) {
         av_log(NULL, AV_LOG_FATAL, "Only video and audio filters supported "
                "currently.\n");

         exit_program(1);

     }
 
     if (in->name) {
         AVFormatContext *s;
         AVStream       *st = NULL;
         char *p;
         int file_idx = strtol(in->name, &p, 0);
 
         if (file_idx < 0 || file_idx >= nb_input_files) {

             av_log(NULL, AV_LOG_FATAL, "Invalid file index %d in filtergraph description %s.\n",

                    file_idx, fg->graph_desc);

             exit_program(1);

         }
         s = input_files[file_idx]->ctx;
 
         for (i = 0; i < s->nb_streams; i++) {

             enum AVMediaType stream_type = s->streams[i]->codecpar->codec_type;

             if (stream_type != type &&
                 !(stream_type == AVMEDIA_TYPE_SUBTITLE &&
                   type == AVMEDIA_TYPE_VIDEO /* sub2video hack */))

                 continue;
             if (check_stream_specifier(s, s->streams[i], *p == ':' ? p + 1 : p) == 1) {
                 st = s->streams[i];
                 break;
             }
         }
         if (!st) {
             av_log(NULL, AV_LOG_FATAL, "Stream specifier '%s' in filtergraph description %s "
                    "matches no streams.\n", p, fg->graph_desc);

             exit_program(1);

         }
         ist = input_streams[input_files[file_idx]->ist_index + st->index];
     } else {
         /* find the first unused stream of corresponding type */
         for (i = 0; i < nb_input_streams; i++) {
             ist = input_streams[i];

             if (ist->dec_ctx->codec_type == type && ist->discard)

                 break;
         }
         if (i == nb_input_streams) {
             av_log(NULL, AV_LOG_FATAL, "Cannot find a matching stream for "

                    "unlabeled input pad %d on filter %s\n", in->pad_idx,

                    in->filter_ctx->name);

             exit_program(1);

         }
     }
     av_assert0(ist);
 
     ist->discard         = 0;

     ist->decoding_needed |= DECODING_FOR_FILTER;

     ist->st->discard = AVDISCARD_NONE;
 

     GROW_ARRAY(fg->inputs, fg->nb_inputs);

     if (!(fg->inputs[fg->nb_inputs - 1] = av_mallocz(sizeof(*fg->inputs[0]))))

         exit_program(1);

     fg->inputs[fg->nb_inputs - 1]->ist   = ist;
     fg->inputs[fg->nb_inputs - 1]->graph = fg;
 

     GROW_ARRAY(ist->filters, ist->nb_filters);

     ist->filters[ist->nb_filters - 1] = fg->inputs[fg->nb_inputs - 1];
 }
 

 int init_complex_filtergraph(FilterGraph *fg)
 {
     AVFilterInOut *inputs, *outputs, *cur;
     AVFilterGraph *graph;
     int ret = 0;
 
     /* this graph is only used for determining the kinds of inputs
      * and outputs we have, and is discarded on exit from this function */
     graph = avfilter_graph_alloc();
     if (!graph)
         return AVERROR(ENOMEM);
 
     ret = avfilter_graph_parse2(graph, fg->graph_desc, &inputs, &outputs);
     if (ret < 0)
         goto fail;
 
     for (cur = inputs; cur; cur = cur->next)
         init_input_filter(fg, cur);
 
     for (cur = outputs; cur;) {
         GROW_ARRAY(fg->outputs, fg->nb_outputs);
         fg->outputs[fg->nb_outputs - 1] = av_mallocz(sizeof(*fg->outputs[0]));
         if (!fg->outputs[fg->nb_outputs - 1])
             exit_program(1);
 
         fg->outputs[fg->nb_outputs - 1]->graph   = fg;
         fg->outputs[fg->nb_outputs - 1]->out_tmp = cur;
         fg->outputs[fg->nb_outputs - 1]->type    = avfilter_pad_get_type(cur->filter_ctx->output_pads,
                                                                          cur->pad_idx);
         cur = cur->next;
         fg->outputs[fg->nb_outputs - 1]->out_tmp->next = NULL;
     }
 
 fail:
     avfilter_inout_free(&inputs);
     avfilter_graph_free(&graph);
     return ret;
 }
 

 static int insert_trim(int64_t start_time, int64_t duration,
                        AVFilterContext **last_filter, int *pad_idx,
                        const char *filter_name)

 {
     AVFilterGraph *graph = (*last_filter)->graph;
     AVFilterContext *ctx;
     const AVFilter *trim;

     enum AVMediaType type = avfilter_pad_get_type((*last_filter)->output_pads, *pad_idx);
     const char *name = (type == AVMEDIA_TYPE_VIDEO) ? "trim" : "atrim";

     int ret = 0;
 

     if (duration == INT64_MAX && start_time == AV_NOPTS_VALUE)

         return 0;
 
     trim = avfilter_get_by_name(name);
     if (!trim) {
         av_log(NULL, AV_LOG_ERROR, "%s filter not present, cannot limit "
                "recording time.\n", name);
         return AVERROR_FILTER_NOT_FOUND;
     }
 
     ctx = avfilter_graph_alloc_filter(graph, trim, filter_name);
     if (!ctx)
         return AVERROR(ENOMEM);
 

     if (duration != INT64_MAX) {

         ret = av_opt_set_int(ctx, "durationi", duration,

                                 AV_OPT_SEARCH_CHILDREN);
     }

     if (ret >= 0 && start_time != AV_NOPTS_VALUE) {

         ret = av_opt_set_int(ctx, "starti", start_time,

                                 AV_OPT_SEARCH_CHILDREN);
     }

     if (ret < 0) {
         av_log(ctx, AV_LOG_ERROR, "Error configuring the %s filter", name);
         return ret;
     }
 
     ret = avfilter_init_str(ctx, NULL);
     if (ret < 0)
         return ret;
 
     ret = avfilter_link(*last_filter, *pad_idx, ctx, 0);
     if (ret < 0)
         return ret;
 
     *last_filter = ctx;
     *pad_idx     = 0;
     return 0;
 }
 

 static int insert_filter(AVFilterContext **last_filter, int *pad_idx,
                          const char *filter_name, const char *args)
 {
     AVFilterGraph *graph = (*last_filter)->graph;
     AVFilterContext *ctx;
     int ret;
 
     ret = avfilter_graph_create_filter(&ctx,
                                        avfilter_get_by_name(filter_name),
                                        filter_name, args, NULL, graph);
     if (ret < 0)
         return ret;
 
     ret = avfilter_link(*last_filter, *pad_idx, ctx, 0);
     if (ret < 0)
         return ret;
 
     *last_filter = ctx;
     *pad_idx     = 0;
     return 0;
 }
 

 static int configure_output_video_filter(FilterGraph *fg, OutputFilter *ofilter, AVFilterInOut *out)
 {
     char *pix_fmts;
     OutputStream *ost = ofilter->ost;

     OutputFile    *of = output_files[ost->file_index];

     AVCodecContext *codec = ost->enc_ctx;

     AVFilterContext *last_filter = out->filter_ctx;
     int pad_idx = out->pad_idx;
     int ret;
     char name[255];
 
     snprintf(name, sizeof(name), "output stream %d:%d", ost->file_index, ost->index);
     ret = avfilter_graph_create_filter(&ofilter->filter,

                                        avfilter_get_by_name("buffersink"),

                                        name, NULL, NULL, fg->graph);

     if (ret < 0)
         return ret;
 

     if (!hw_device_ctx && (codec->width || codec->height)) {

         char args[255];
         AVFilterContext *filter;

         AVDictionaryEntry *e = NULL;

         snprintf(args, sizeof(args), "%d:%d",

                  codec->width,

                  codec->height);
 
         while ((e = av_dict_get(ost->sws_dict, "", e,
                                 AV_DICT_IGNORE_SUFFIX))) {
             av_strlcatf(args, sizeof(args), ":%s=%s", e->key, e->value);
         }
 

         snprintf(name, sizeof(name), "scaler for output stream %d:%d",
                  ost->file_index, ost->index);
         if ((ret = avfilter_graph_create_filter(&filter, avfilter_get_by_name("scale"),
                                                 name, args, NULL, fg->graph)) < 0)
             return ret;
         if ((ret = avfilter_link(last_filter, pad_idx, filter, 0)) < 0)
             return ret;
 
         last_filter = filter;
         pad_idx = 0;
     }
 
     if ((pix_fmts = choose_pix_fmts(ost))) {
         AVFilterContext *filter;
         snprintf(name, sizeof(name), "pixel format for output stream %d:%d",
                  ost->file_index, ost->index);

         ret = avfilter_graph_create_filter(&filter,

                                            avfilter_get_by_name("format"),
                                            "format", pix_fmts, NULL, fg->graph);

         av_freep(&pix_fmts);
         if (ret < 0)

             return ret;
         if ((ret = avfilter_link(last_filter, pad_idx, filter, 0)) < 0)
             return ret;
 
         last_filter = filter;
         pad_idx     = 0;
     }
 

     if (ost->frame_rate.num && 0) {

         AVFilterContext *fps;
         char args[255];
 
         snprintf(args, sizeof(args), "fps=%d/%d", ost->frame_rate.num,
                  ost->frame_rate.den);
         snprintf(name, sizeof(name), "fps for output stream %d:%d",
                  ost->file_index, ost->index);
         ret = avfilter_graph_create_filter(&fps, avfilter_get_by_name("fps"),
                                            name, args, NULL, fg->graph);
         if (ret < 0)
             return ret;
 
         ret = avfilter_link(last_filter, pad_idx, fps, 0);
         if (ret < 0)
             return ret;
         last_filter = fps;
         pad_idx = 0;
     }
 

     snprintf(name, sizeof(name), "trim for output stream %d:%d",
              ost->file_index, ost->index);
     ret = insert_trim(of->start_time, of->recording_time,
                       &last_filter, &pad_idx, name);

     if (ret < 0)
         return ret;
 
 

     if ((ret = avfilter_link(last_filter, pad_idx, ofilter->filter, 0)) < 0)
         return ret;
 
     return 0;
 }
 
 static int configure_output_audio_filter(FilterGraph *fg, OutputFilter *ofilter, AVFilterInOut *out)
 {
     OutputStream *ost = ofilter->ost;

     OutputFile    *of = output_files[ost->file_index];

     AVCodecContext *codec  = ost->enc_ctx;

     AVFilterContext *last_filter = out->filter_ctx;
     int pad_idx = out->pad_idx;
     char *sample_fmts, *sample_rates, *channel_layouts;
     char name[255];
     int ret;
 
     snprintf(name, sizeof(name), "output stream %d:%d", ost->file_index, ost->index);
     ret = avfilter_graph_create_filter(&ofilter->filter,

                                        avfilter_get_by_name("abuffersink"),

                                        name, NULL, NULL, fg->graph);

     if (ret < 0)
         return ret;

     if ((ret = av_opt_set_int(ofilter->filter, "all_channel_counts", 1, AV_OPT_SEARCH_CHILDREN)) < 0)
         return ret;

 #define AUTO_INSERT_FILTER(opt_name, filter_name, arg) do {                 \
     AVFilterContext *filt_ctx;                                              \
                                                                             \
     av_log(NULL, AV_LOG_INFO, opt_name " is forwarded to lavfi "            \
            "similarly to -af " filter_name "=%s.\n", arg);                  \
                                                                             \
     ret = avfilter_graph_create_filter(&filt_ctx,                           \
                                        avfilter_get_by_name(filter_name),   \
                                        filter_name, arg, NULL, fg->graph);  \
     if (ret < 0)                                                            \
         return ret;                                                         \
                                                                             \
     ret = avfilter_link(last_filter, pad_idx, filt_ctx, 0);                 \
     if (ret < 0)                                                            \
         return ret;                                                         \
                                                                             \
     last_filter = filt_ctx;                                                 \
     pad_idx = 0;                                                            \
 } while (0)
     if (ost->audio_channels_mapped) {
         int i;
         AVBPrint pan_buf;
         av_bprint_init(&pan_buf, 256, 8192);
         av_bprintf(&pan_buf, "0x%"PRIx64,
                    av_get_default_channel_layout(ost->audio_channels_mapped));
         for (i = 0; i < ost->audio_channels_mapped; i++)
             if (ost->audio_channels_map[i] != -1)

                 av_bprintf(&pan_buf, "|c%d=c%d", i, ost->audio_channels_map[i]);

 
         AUTO_INSERT_FILTER("-map_channel", "pan", pan_buf.str);
         av_bprint_finalize(&pan_buf, NULL);
     }
 

     if (codec->channels && !codec->channel_layout)
         codec->channel_layout = av_get_default_channel_layout(codec->channels);
 
     sample_fmts     = choose_sample_fmts(ost);
     sample_rates    = choose_sample_rates(ost);
     channel_layouts = choose_channel_layouts(ost);
     if (sample_fmts || sample_rates || channel_layouts) {
         AVFilterContext *format;
         char args[256];

         args[0] = 0;

 
         if (sample_fmts)

             av_strlcatf(args, sizeof(args), "sample_fmts=%s:",

                             sample_fmts);
         if (sample_rates)

             av_strlcatf(args, sizeof(args), "sample_rates=%s:",

                             sample_rates);
         if (channel_layouts)

             av_strlcatf(args, sizeof(args), "channel_layouts=%s:",

                             channel_layouts);
 
         av_freep(&sample_fmts);
         av_freep(&sample_rates);
         av_freep(&channel_layouts);
 
         snprintf(name, sizeof(name), "audio format for output stream %d:%d",
                  ost->file_index, ost->index);
         ret = avfilter_graph_create_filter(&format,
                                            avfilter_get_by_name("aformat"),
                                            name, args, NULL, fg->graph);
         if (ret < 0)
             return ret;
 
         ret = avfilter_link(last_filter, pad_idx, format, 0);
         if (ret < 0)
             return ret;
 
         last_filter = format;
         pad_idx = 0;
     }
 

     if (audio_volume != 256 && 0) {
         char args[256];
 
         snprintf(args, sizeof(args), "%f", audio_volume / 256.);
         AUTO_INSERT_FILTER("-vol", "volume", args);
     }
 

     if (ost->apad && of->shortest) {
         char args[256];
         int i;
 
         for (i=0; i<of->ctx->nb_streams; i++)

             if (of->ctx->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_VIDEO)

                 break;
 
         if (i<of->ctx->nb_streams) {
             snprintf(args, sizeof(args), "%s", ost->apad);
             AUTO_INSERT_FILTER("-apad", "apad", args);
         }
     }
 

     snprintf(name, sizeof(name), "trim for output stream %d:%d",
              ost->file_index, ost->index);
     ret = insert_trim(of->start_time, of->recording_time,
                       &last_filter, &pad_idx, name);

     if (ret < 0)
         return ret;
 

     if ((ret = avfilter_link(last_filter, pad_idx, ofilter->filter, 0)) < 0)
         return ret;
 
     return 0;
 }
 
 #define DESCRIBE_FILTER_LINK(f, inout, in)                         \
 {                                                                  \
     AVFilterContext *ctx = inout->filter_ctx;                      \
     AVFilterPad *pads = in ? ctx->input_pads  : ctx->output_pads;  \

     int       nb_pads = in ? ctx->nb_inputs   : ctx->nb_outputs;   \

     AVIOContext *pb;                                               \
                                                                    \
     if (avio_open_dyn_buf(&pb) < 0)                                \

         exit_program(1);                                           \

                                                                    \
     avio_printf(pb, "%s", ctx->filter->name);                      \
     if (nb_pads > 1)                                               \
         avio_printf(pb, ":%s", avfilter_pad_get_name(pads, inout->pad_idx));\
     avio_w8(pb, 0);                                                \
     avio_close_dyn_buf(pb, &f->name);                              \
 }
 
 int configure_output_filter(FilterGraph *fg, OutputFilter *ofilter, AVFilterInOut *out)
 {
     av_freep(&ofilter->name);
     DESCRIBE_FILTER_LINK(ofilter, out, 0);
 

     if (!ofilter->ost) {

         av_log(NULL, AV_LOG_FATAL, "Filter %s has an unconnected output\n", ofilter->name);

         exit_program(1);
     }
 

     switch (avfilter_pad_get_type(out->filter_ctx->output_pads, out->pad_idx)) {
     case AVMEDIA_TYPE_VIDEO: return configure_output_video_filter(fg, ofilter, out);
     case AVMEDIA_TYPE_AUDIO: return configure_output_audio_filter(fg, ofilter, out);
     default: av_assert0(0);
     }
 }
 

 static int sub2video_prepare(InputStream *ist)
 {
     AVFormatContext *avf = input_files[ist->file_index]->ctx;

     int i, w, h;

 
     /* Compute the size of the canvas for the subtitles stream.

        If the subtitles codecpar has set a size, use it. Otherwise use the

        maximum dimensions of the video streams in the same file. */

     w = ist->dec_ctx->width;
     h = ist->dec_ctx->height;

     if (!(w && h)) {
         for (i = 0; i < avf->nb_streams; i++) {

             if (avf->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) {
                 w = FFMAX(w, avf->streams[i]->codecpar->width);
                 h = FFMAX(h, avf->streams[i]->codecpar->height);

             }
         }
         if (!(w && h)) {
             w = FFMAX(w, 720);
             h = FFMAX(h, 576);
         }
         av_log(avf, AV_LOG_INFO, "sub2video: using %dx%d canvas\n", w, h);
     }

     ist->sub2video.w = ist->resample_width  = w;
     ist->sub2video.h = ist->resample_height = h;

     /* rectangles are AV_PIX_FMT_PAL8, but we have no guarantee that the

        palettes for all rectangles are identical or compatible */

     ist->resample_pix_fmt = ist->dec_ctx->pix_fmt = AV_PIX_FMT_RGB32;

     ist->sub2video.frame = av_frame_alloc();
     if (!ist->sub2video.frame)

         return AVERROR(ENOMEM);

     ist->sub2video.last_pts = INT64_MIN;

     return 0;
 }
 

 static int configure_input_video_filter(FilterGraph *fg, InputFilter *ifilter,
                                         AVFilterInOut *in)
 {

     AVFilterContext *last_filter;

     const AVFilter *buffer_filt = avfilter_get_by_name("buffer");

     InputStream *ist = ifilter->ist;

     InputFile     *f = input_files[ist->file_index];

     AVRational tb = ist->framerate.num ? av_inv_q(ist->framerate) :
                                          ist->st->time_base;

     AVRational fr = ist->framerate;

     AVRational sar;

     AVBPrint args;
     char name[255];

     int ret, pad_idx = 0;

     int64_t tsoffset = 0;

     AVBufferSrcParameters *par = av_buffersrc_parameters_alloc();
 
     if (!par)
         return AVERROR(ENOMEM);
     memset(par, 0, sizeof(*par));
     par->format = AV_PIX_FMT_NONE;

     if (ist->dec_ctx->codec_type == AVMEDIA_TYPE_AUDIO) {

         av_log(NULL, AV_LOG_ERROR, "Cannot connect video filter to audio input\n");

         ret = AVERROR(EINVAL);
         goto fail;

     }
 

     if (!fr.num)
         fr = av_guess_frame_rate(input_files[ist->file_index]->ctx, ist->st, NULL);

     if (ist->dec_ctx->codec_type == AVMEDIA_TYPE_SUBTITLE) {

         ret = sub2video_prepare(ist);
         if (ret < 0)

             goto fail;

     }
 

     sar = ist->st->sample_aspect_ratio.num ?
           ist->st->sample_aspect_ratio :

           ist->dec_ctx->sample_aspect_ratio;

     if(!sar.den)
         sar = (AVRational){0,1};
     av_bprint_init(&args, 0, 1);
     av_bprintf(&args,
              "video_size=%dx%d:pix_fmt=%d:time_base=%d/%d:"

              "pixel_aspect=%d/%d:sws_param=flags=%d", ist->resample_width,

              ist->resample_height,
              ist->hwaccel_retrieve_data ? ist->hwaccel_retrieved_pix_fmt : ist->resample_pix_fmt,

              tb.num, tb.den, sar.num, sar.den,

              SWS_BILINEAR + ((ist->dec_ctx->flags&AV_CODEC_FLAG_BITEXACT) ? SWS_BITEXACT:0));

     if (fr.num && fr.den)
         av_bprintf(&args, ":frame_rate=%d/%d", fr.num, fr.den);

     snprintf(name, sizeof(name), "graph %d input from stream %d:%d", fg->index,
              ist->file_index, ist->st->index);
 

     if ((ret = avfilter_graph_create_filter(&ifilter->filter, buffer_filt, name,

                                             args.str, NULL, fg->graph)) < 0)

         goto fail;

     par->hw_frames_ctx = ist->hw_frames_ctx;
     ret = av_buffersrc_parameters_set(ifilter->filter, par);
     if (ret < 0)

         goto fail;

     av_freep(&par);

     last_filter = ifilter->filter;

     if (ist->autorotate) {

         double theta = get_rotation(ist->st);
 
         if (fabs(theta - 90) < 1.0) {
             ret = insert_filter(&last_filter, &pad_idx, "transpose", "clock");
         } else if (fabs(theta - 180) < 1.0) {
             ret = insert_filter(&last_filter, &pad_idx, "hflip", NULL);

             if (ret < 0)
                 return ret;

             ret = insert_filter(&last_filter, &pad_idx, "vflip", NULL);
         } else if (fabs(theta - 270) < 1.0) {
             ret = insert_filter(&last_filter, &pad_idx, "transpose", "cclock");
         } else if (fabs(theta) > 1.0) {
             char rotate_buf[64];
             snprintf(rotate_buf, sizeof(rotate_buf), "%f*PI/180", theta);
             ret = insert_filter(&last_filter, &pad_idx, "rotate", rotate_buf);

         }

         if (ret < 0)
             return ret;

     }
 

     if (ist->framerate.num) {
         AVFilterContext *setpts;
 
         snprintf(name, sizeof(name), "force CFR for input from stream %d:%d",
                  ist->file_index, ist->st->index);
         if ((ret = avfilter_graph_create_filter(&setpts,
                                                 avfilter_get_by_name("setpts"),
                                                 name, "N", NULL,
                                                 fg->graph)) < 0)
             return ret;
 

         if ((ret = avfilter_link(last_filter, 0, setpts, 0)) < 0)

             return ret;
 

         last_filter = setpts;

     }
 

     if (do_deinterlace) {
         AVFilterContext *yadif;
 
         snprintf(name, sizeof(name), "deinterlace input from stream %d:%d",
                  ist->file_index, ist->st->index);
         if ((ret = avfilter_graph_create_filter(&yadif,
                                                 avfilter_get_by_name("yadif"),
                                                 name, "", NULL,
                                                 fg->graph)) < 0)
             return ret;
 

         if ((ret = avfilter_link(last_filter, 0, yadif, 0)) < 0)

             return ret;
 

         last_filter = yadif;

     }
 

     snprintf(name, sizeof(name), "trim for input stream %d:%d",
              ist->file_index, ist->st->index);

     if (copy_ts) {
         tsoffset = f->start_time == AV_NOPTS_VALUE ? 0 : f->start_time;
         if (!start_at_zero && f->ctx->start_time != AV_NOPTS_VALUE)
             tsoffset += f->ctx->start_time;
     }

     ret = insert_trim(((f->start_time == AV_NOPTS_VALUE) || !f->accurate_seek) ?

                       AV_NOPTS_VALUE : tsoffset, f->recording_time,
                       &last_filter, &pad_idx, name);

     if (ret < 0)
         return ret;
 

     if ((ret = avfilter_link(last_filter, 0, in->filter_ctx, in->pad_idx)) < 0)

         return ret;
     return 0;

 fail:
     av_freep(&par);
 
     return ret;

 }
 
 static int configure_input_audio_filter(FilterGraph *fg, InputFilter *ifilter,
                                         AVFilterInOut *in)
 {

     AVFilterContext *last_filter;

     const AVFilter *abuffer_filt = avfilter_get_by_name("abuffer");

     InputStream *ist = ifilter->ist;

     InputFile     *f = input_files[ist->file_index];

     AVBPrint args;
     char name[255];

     int ret, pad_idx = 0;

     int64_t tsoffset = 0;

     if (ist->dec_ctx->codec_type != AVMEDIA_TYPE_AUDIO) {

         av_log(NULL, AV_LOG_ERROR, "Cannot connect audio filter to non audio input\n");
         return AVERROR(EINVAL);
     }
 

     av_bprint_init(&args, 0, AV_BPRINT_SIZE_AUTOMATIC);
     av_bprintf(&args, "time_base=%d/%d:sample_rate=%d:sample_fmt=%s",

              1, ist->dec_ctx->sample_rate,
              ist->dec_ctx->sample_rate,

              av_get_sample_fmt_name(ist->dec_ctx->sample_fmt));
     if (ist->dec_ctx->channel_layout)

         av_bprintf(&args, ":channel_layout=0x%"PRIx64,

                    ist->dec_ctx->channel_layout);

     else

         av_bprintf(&args, ":channels=%d", ist->dec_ctx->channels);

     snprintf(name, sizeof(name), "graph %d input from stream %d:%d", fg->index,
              ist->file_index, ist->st->index);
 

     if ((ret = avfilter_graph_create_filter(&ifilter->filter, abuffer_filt,

                                             name, args.str, NULL,

                                             fg->graph)) < 0)
         return ret;

     last_filter = ifilter->filter;

 #define AUTO_INSERT_FILTER_INPUT(opt_name, filter_name, arg) do {                 \
     AVFilterContext *filt_ctx;                                              \
                                                                             \
     av_log(NULL, AV_LOG_INFO, opt_name " is forwarded to lavfi "            \
            "similarly to -af " filter_name "=%s.\n", arg);                  \
                                                                             \
     snprintf(name, sizeof(name), "graph %d %s for input stream %d:%d",      \
                 fg->index, filter_name, ist->file_index, ist->st->index);   \
     ret = avfilter_graph_create_filter(&filt_ctx,                           \
                                        avfilter_get_by_name(filter_name),   \
                                        name, arg, NULL, fg->graph);         \
     if (ret < 0)                                                            \
         return ret;                                                         \
                                                                             \

     ret = avfilter_link(last_filter, 0, filt_ctx, 0);                       \

     if (ret < 0)                                                            \
         return ret;                                                         \
                                                                             \

     last_filter = filt_ctx;                                                 \

 } while (0)

     if (audio_sync_method > 0) {
         char args[256] = {0};

         av_strlcatf(args, sizeof(args), "async=%d", audio_sync_method);
         if (audio_drift_threshold != 0.1)
             av_strlcatf(args, sizeof(args), ":min_hard_comp=%f", audio_drift_threshold);

         if (!fg->reconfiguration)
             av_strlcatf(args, sizeof(args), ":first_pts=0");

         AUTO_INSERT_FILTER_INPUT("-async", "aresample", args);
     }

 //     if (ost->audio_channels_mapped) {
 //         int i;
 //         AVBPrint pan_buf;
 //         av_bprint_init(&pan_buf, 256, 8192);
 //         av_bprintf(&pan_buf, "0x%"PRIx64,
 //                    av_get_default_channel_layout(ost->audio_channels_mapped));
 //         for (i = 0; i < ost->audio_channels_mapped; i++)
 //             if (ost->audio_channels_map[i] != -1)
 //                 av_bprintf(&pan_buf, ":c%d=c%d", i, ost->audio_channels_map[i]);
 //         AUTO_INSERT_FILTER_INPUT("-map_channel", "pan", pan_buf.str);
 //         av_bprint_finalize(&pan_buf, NULL);
 //     }
 
     if (audio_volume != 256) {
         char args[256];

         av_log(NULL, AV_LOG_WARNING, "-vol has been deprecated. Use the volume "
                "audio filter instead.\n");
 

         snprintf(args, sizeof(args), "%f", audio_volume / 256.);
         AUTO_INSERT_FILTER_INPUT("-vol", "volume", args);

     }

 
     snprintf(name, sizeof(name), "trim for input stream %d:%d",
              ist->file_index, ist->st->index);

     if (copy_ts) {
         tsoffset = f->start_time == AV_NOPTS_VALUE ? 0 : f->start_time;
         if (!start_at_zero && f->ctx->start_time != AV_NOPTS_VALUE)
             tsoffset += f->ctx->start_time;
     }

     ret = insert_trim(((f->start_time == AV_NOPTS_VALUE) || !f->accurate_seek) ?

                       AV_NOPTS_VALUE : tsoffset, f->recording_time,
                       &last_filter, &pad_idx, name);

     if (ret < 0)
         return ret;
 

     if ((ret = avfilter_link(last_filter, 0, in->filter_ctx, in->pad_idx)) < 0)

         return ret;
 
     return 0;
 }
 
 static int configure_input_filter(FilterGraph *fg, InputFilter *ifilter,
                                   AVFilterInOut *in)
 {
     av_freep(&ifilter->name);
     DESCRIBE_FILTER_LINK(ifilter, in, 1);
 

     if (!ifilter->ist->dec) {
         av_log(NULL, AV_LOG_ERROR,
                "No decoder for stream #%d:%d, filtering impossible\n",
                ifilter->ist->file_index, ifilter->ist->st->index);
         return AVERROR_DECODER_NOT_FOUND;
     }

     switch (avfilter_pad_get_type(in->filter_ctx->input_pads, in->pad_idx)) {
     case AVMEDIA_TYPE_VIDEO: return configure_input_video_filter(fg, ifilter, in);
     case AVMEDIA_TYPE_AUDIO: return configure_input_audio_filter(fg, ifilter, in);
     default: av_assert0(0);
     }
 }
 
 int configure_filtergraph(FilterGraph *fg)
 {
     AVFilterInOut *inputs, *outputs, *cur;

     int ret, i, simple = filtergraph_is_simple(fg);

     const char *graph_desc = simple ? fg->outputs[0]->ost->avfilter :
                                       fg->graph_desc;
 
     avfilter_graph_free(&fg->graph);
     if (!(fg->graph = avfilter_graph_alloc()))
         return AVERROR(ENOMEM);
 
     if (simple) {
         OutputStream *ost = fg->outputs[0]->ost;

         char args[512];
         AVDictionaryEntry *e = NULL;
 

         args[0] = 0;
         while ((e = av_dict_get(ost->sws_dict, "", e,
                                 AV_DICT_IGNORE_SUFFIX))) {
             av_strlcatf(args, sizeof(args), "%s=%s:", e->key, e->value);
         }
         if (strlen(args))
             args[strlen(args)-1] = 0;

         fg->graph->scale_sws_opts = av_strdup(args);

 
         args[0] = 0;

         while ((e = av_dict_get(ost->swr_opts, "", e,
                                 AV_DICT_IGNORE_SUFFIX))) {
             av_strlcatf(args, sizeof(args), "%s=%s:", e->key, e->value);
         }

         if (strlen(args))
             args[strlen(args)-1] = 0;
         av_opt_set(fg->graph, "aresample_swr_opts", args, 0);

 
         args[0] = '\0';
         while ((e = av_dict_get(fg->outputs[0]->ost->resample_opts, "", e,
                                 AV_DICT_IGNORE_SUFFIX))) {
             av_strlcatf(args, sizeof(args), "%s=%s:", e->key, e->value);
         }
         if (strlen(args))
             args[strlen(args) - 1] = '\0';
         fg->graph->resample_lavr_opts = av_strdup(args);

         e = av_dict_get(ost->encoder_opts, "threads", NULL, 0);

         if (e)
             av_opt_set(fg->graph, "threads", e->value, 0);

     }
 
     if ((ret = avfilter_graph_parse2(fg->graph, graph_desc, &inputs, &outputs)) < 0)
         return ret;
 

     if (hw_device_ctx) {
         for (i = 0; i < fg->graph->nb_filters; i++) {
             fg->graph->filters[i]->hw_device_ctx = av_buffer_ref(hw_device_ctx);
         }
     }
 

     if (simple && (!inputs || inputs->next || !outputs || outputs->next)) {

         const char *num_inputs;
         const char *num_outputs;
         if (!outputs) {
             num_outputs = "0";
         } else if (outputs->next) {
             num_outputs = ">1";
         } else {
             num_outputs = "1";
         }
         if (!inputs) {
             num_inputs = "0";
         } else if (inputs->next) {
             num_inputs = ">1";
         } else {
             num_inputs = "1";
         }
         av_log(NULL, AV_LOG_ERROR, "Simple filtergraph '%s' was expected "
                "to have exactly 1 input and 1 output."
                " However, it had %s input(s) and %s output(s)."
                " Please adjust, or use a complex filtergraph (-filter_complex) instead.\n",
                graph_desc, num_inputs, num_outputs);

         return AVERROR(EINVAL);
     }
 
     for (cur = inputs, i = 0; cur; cur = cur->next, i++)

         if ((ret = configure_input_filter(fg, fg->inputs[i], cur)) < 0) {
             avfilter_inout_free(&inputs);
             avfilter_inout_free(&outputs);

             return ret;

         }

     avfilter_inout_free(&inputs);
 

     for (cur = outputs, i = 0; cur; cur = cur->next, i++)
         configure_output_filter(fg, fg->outputs[i], cur);

     avfilter_inout_free(&outputs);

     if ((ret = avfilter_graph_config(fg->graph, NULL)) < 0)
         return ret;

     fg->reconfiguration = 1;

 
     for (i = 0; i < fg->nb_outputs; i++) {
         OutputStream *ost = fg->outputs[i]->ost;

         if (!ost->enc) {
             /* identical to the same check in ffmpeg.c, needed because
                complex filter graphs are initialized earlier */
             av_log(NULL, AV_LOG_ERROR, "Encoder (codec %s) not found for output stream #%d:%d\n",

                      avcodec_get_name(ost->st->codecpar->codec_id), ost->file_index, ost->index);

             return AVERROR(EINVAL);
         }

         if (ost->enc->type == AVMEDIA_TYPE_AUDIO &&

             !(ost->enc->capabilities & AV_CODEC_CAP_VARIABLE_FRAME_SIZE))

             av_buffersink_set_frame_size(ost->filter->filter,
                                          ost->enc_ctx->frame_size);
     }
 

     return 0;
 }
 
 int ist_in_filtergraph(FilterGraph *fg, InputStream *ist)
 {
     int i;
     for (i = 0; i < fg->nb_inputs; i++)
         if (fg->inputs[i]->ist == ist)
             return 1;
     return 0;
 }
 

 int filtergraph_is_simple(FilterGraph *fg)
 {
     return !fg->graph_desc;
 }