avconv: split configuring filter configuration to a separate file.

4 files changed, 563 insertions, 530 deletions

diff --git a/Makefile b/Makefile
index 6477059c3f..1a4858d08d 100644
--- a/Makefile
+++ b/Makefile
@@ -60,7 +60,7 @@ PROGS-$(CONFIG_AVSERVER) += avserver
 
 PROGS      := $(PROGS-yes:%=%$(EXESUF))
 OBJS        = cmdutils.o
-OBJS-avconv = avconv_opt.o
+OBJS-avconv = avconv_opt.o avconv_filter.o
 TESTTOOLS   = audiogen videogen rotozoom tiny_psnr base64
 HOSTPROGS  := $(TESTTOOLS:%=tests/%) doc/print_options
 TOOLS       = qt-faststart trasher
diff --git a/avconv.c b/avconv.c
index ad4a975a1c..3b50dd4db1 100644
--- a/avconv.c
+++ b/avconv.c
@@ -111,535 +111,6 @@ int         nb_output_files   = 0;
 FilterGraph **filtergraphs;
 int        nb_filtergraphs;
 
-/**
- * Define a function for building a string containing a list of
- * allowed formats,
- */
-#define DEF_CHOOSE_FORMAT(type, var, supported_list, none, get_name, separator) \
-static char *choose_ ## var ## s(OutputStream *ost)                             \
-{                                                                               \
-    if (ost->st->codec->var != none) {                                          \
-        get_name(ost->st->codec->var);                                          \
-        return av_strdup(name);                                                 \
-    } else if (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" separator, name);                               \
-        }                                                                       \
-        len = avio_close_dyn_buf(s, &ret);                                      \
-        ret[len - 1] = 0;                                                       \
-        return ret;                                                             \
-    } else                                                                      \
-        return NULL;                                                            \
-}
-
-#define GET_PIX_FMT_NAME(pix_fmt)\
-    const char *name = av_get_pix_fmt_name(pix_fmt);
-
-DEF_CHOOSE_FORMAT(enum PixelFormat, pix_fmt, pix_fmts, PIX_FMT_NONE,
-                  GET_PIX_FMT_NAME, ":")
-
-#define GET_SAMPLE_FMT_NAME(sample_fmt)\
-    const char *name = av_get_sample_fmt_name(sample_fmt)
-
-DEF_CHOOSE_FORMAT(enum AVSampleFormat, sample_fmt, sample_fmts,
-                  AV_SAMPLE_FMT_NONE, GET_SAMPLE_FMT_NAME, ",")
-
-#define GET_SAMPLE_RATE_NAME(rate)\
-    char name[16];\
-    snprintf(name, sizeof(name), "%d", rate);
-
-DEF_CHOOSE_FORMAT(int, sample_rate, supported_samplerates, 0,
-                  GET_SAMPLE_RATE_NAME, ",")
-
-#define GET_CH_LAYOUT_NAME(ch_layout)\
-    char name[16];\
-    snprintf(name, sizeof(name), "0x%"PRIx64, ch_layout);
-
-DEF_CHOOSE_FORMAT(uint64_t, channel_layout, channel_layouts, 0,
-                  GET_CH_LAYOUT_NAME, ",")
-
-static FilterGraph *init_simple_filtergraph(InputStream *ist, OutputStream *ost)
-{
-    FilterGraph *fg = av_mallocz(sizeof(*fg));
-
-    if (!fg)
-        exit_program(1);
-    fg->index = nb_filtergraphs;
-
-    fg->outputs = grow_array(fg->outputs, sizeof(*fg->outputs), &fg->nb_outputs,
-                             fg->nb_outputs + 1);
-    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];
-
-    fg->inputs = grow_array(fg->inputs, sizeof(*fg->inputs), &fg->nb_inputs,
-                            fg->nb_inputs + 1);
-    if (!(fg->inputs[0] = av_mallocz(sizeof(*fg->inputs[0]))))
-        exit_program(1);
-    fg->inputs[0]->ist   = ist;
-    fg->inputs[0]->graph = fg;
-
-    ist->filters = grow_array(ist->filters, sizeof(*ist->filters),
-                              &ist->nb_filters, ist->nb_filters + 1);
-    ist->filters[ist->nb_filters - 1] = fg->inputs[0];
-
-    filtergraphs = grow_array(filtergraphs, sizeof(*filtergraphs),
-                              &nb_filtergraphs, nb_filtergraphs + 1);
-    filtergraphs[nb_filtergraphs - 1] = fg;
-
-    return fg;
-}
-
-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 filtegraph 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++) {
-            if (s->streams[i]->codec->codec_type != type)
-                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->st->codec->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", in->pad_idx,
-                   in->filter_ctx->name);
-            exit_program(1);
-        }
-    }
-    av_assert0(ist);
-
-    ist->discard         = 0;
-    ist->decoding_needed = 1;
-    ist->st->discard = AVDISCARD_NONE;
-
-    fg->inputs = grow_array(fg->inputs, sizeof(*fg->inputs),
-                            &fg->nb_inputs, fg->nb_inputs + 1);
-    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;
-
-    ist->filters = grow_array(ist->filters, sizeof(*ist->filters),
-                              &ist->nb_filters, ist->nb_filters + 1);
-    ist->filters[ist->nb_filters - 1] = fg->inputs[fg->nb_inputs - 1];
-}
-
-static int configure_output_video_filter(FilterGraph *fg, OutputFilter *ofilter, AVFilterInOut *out)
-{
-    char *pix_fmts;
-    OutputStream *ost = ofilter->ost;
-    AVCodecContext *codec = ost->st->codec;
-    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, pix_fmts, fg->graph);
-    if (ret < 0)
-        return ret;
-
-    if (codec->width || codec->height) {
-        char args[255];
-        AVFilterContext *filter;
-
-        snprintf(args, sizeof(args), "%d:%d:flags=0x%X",
-                 codec->width,
-                 codec->height,
-                 (unsigned)ost->sws_flags);
-        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);
-        if ((ret = avfilter_graph_create_filter(&filter,
-                                                avfilter_get_by_name("format"),
-                                                "format", pix_fmts, 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;
-        av_freep(&pix_fmts);
-    }
-
-    if (ost->frame_rate.num) {
-        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;
-    }
-
-    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;
-    AVCodecContext *codec  = ost->st->codec;
-    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 (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];
-        int len = 0;
-
-        if (sample_fmts)
-            len += snprintf(args + len, sizeof(args) - len, "sample_fmts=%s:",
-                            sample_fmts);
-        if (sample_rates)
-            len += snprintf(args + len, sizeof(args) - len, "sample_rates=%s:",
-                            sample_rates);
-        if (channel_layouts)
-            len += snprintf(args + len, sizeof(args) - len, "channel_layouts=%s:",
-                            channel_layouts);
-        args[len - 1] = 0;
-
-        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 ((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->input_count : ctx->output_count; \
-    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);
-
-    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 configure_input_video_filter(FilterGraph *fg, InputFilter *ifilter,
-                                        AVFilterInOut *in)
-{
-    AVFilterContext *first_filter = in->filter_ctx;
-    AVFilter *filter = avfilter_get_by_name("buffer");
-    InputStream *ist = ifilter->ist;
-    AVRational tb = ist->framerate.num ? av_inv_q(ist->framerate) :
-                                         ist->st->time_base;
-    AVRational sar;
-    char args[255], name[255];
-    int pad_idx = in->pad_idx;
-    int ret;
-
-    sar = ist->st->sample_aspect_ratio.num ?
-          ist->st->sample_aspect_ratio :
-          ist->st->codec->sample_aspect_ratio;
-    snprintf(args, sizeof(args), "%d:%d:%d:%d:%d:%d:%d", ist->st->codec->width,
-             ist->st->codec->height, ist->st->codec->pix_fmt,
-             tb.num, tb.den, sar.num, sar.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, filter, name,
-                                            args, NULL, fg->graph)) < 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(setpts, 0, first_filter, pad_idx)) < 0)
-            return ret;
-
-        first_filter = setpts;
-        pad_idx = 0;
-    }
-
-    if ((ret = avfilter_link(ifilter->filter, 0, first_filter, pad_idx)) < 0)
-        return ret;
-    return 0;
-}
-
-static int configure_input_audio_filter(FilterGraph *fg, InputFilter *ifilter,
-                                        AVFilterInOut *in)
-{
-    AVFilterContext *first_filter = in->filter_ctx;
-    AVFilter *filter = avfilter_get_by_name("abuffer");
-    InputStream *ist = ifilter->ist;
-    int pad_idx = in->pad_idx;
-    char args[255], name[255];
-    int ret;
-
-    snprintf(args, sizeof(args), "time_base=%d/%d:sample_rate=%d:sample_fmt=%s"
-             ":channel_layout=0x%"PRIx64,
-             1, ist->st->codec->sample_rate,
-             ist->st->codec->sample_rate,
-             av_get_sample_fmt_name(ist->st->codec->sample_fmt),
-             ist->st->codec->channel_layout);
-    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, filter,
-                                            name, args, NULL,
-                                            fg->graph)) < 0)
-        return ret;
-
-    if (audio_sync_method > 0) {
-        AVFilterContext *async;
-        char args[256];
-        int  len = 0;
-
-        av_log(NULL, AV_LOG_WARNING, "-async has been deprecated. Used the "
-               "asyncts audio filter instead.\n");
-
-        if (audio_sync_method > 1)
-            len += snprintf(args + len, sizeof(args) - len, "compensate=1:"
-                            "max_comp=%d:", audio_sync_method);
-        snprintf(args + len, sizeof(args) - len, "min_delta=%f",
-                 audio_drift_threshold);
-
-        snprintf(name, sizeof(name), "graph %d audio sync for input stream %d:%d",
-                 fg->index, ist->file_index, ist->st->index);
-        ret = avfilter_graph_create_filter(&async,
-                                           avfilter_get_by_name("asyncts"),
-                                           name, args, NULL, fg->graph);
-        if (ret < 0)
-            return ret;
-
-        ret = avfilter_link(async, 0, first_filter, pad_idx);
-        if (ret < 0)
-            return ret;
-
-        first_filter = async;
-        pad_idx = 0;
-    }
-    if ((ret = avfilter_link(ifilter->filter, 0, first_filter, 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);
-
-    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, init = !fg->graph, simple = !fg->graph_desc;
-    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[255];
-        snprintf(args, sizeof(args), "flags=0x%X", (unsigned)ost->sws_flags);
-        fg->graph->scale_sws_opts = av_strdup(args);
-    }
-
-    if ((ret = avfilter_graph_parse2(fg->graph, graph_desc, &inputs, &outputs)) < 0)
-        return ret;
-
-    if (simple && (!inputs || inputs->next || !outputs || outputs->next)) {
-        av_log(NULL, AV_LOG_ERROR, "Simple filtergraph '%s' does not have "
-               "exactly one input and output.\n", graph_desc);
-        return AVERROR(EINVAL);
-    }
-
-    for (cur = inputs; !simple && init && cur; cur = cur->next)
-        init_input_filter(fg, cur);
-
-    for (cur = inputs, i = 0; cur; cur = cur->next, i++)
-        if ((ret = configure_input_filter(fg, fg->inputs[i], cur)) < 0)
-            return ret;
-    avfilter_inout_free(&inputs);
-
-    if (!init || simple) {
-        /* we already know the mappings between lavfi outputs and output streams,
-         * so we can finish the setup */
-        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;
-    } else {
-        /* wait until output mappings are processed */
-        for (cur = outputs; cur;) {
-            fg->outputs = grow_array(fg->outputs, sizeof(*fg->outputs),
-                                     &fg->nb_outputs, fg->nb_outputs + 1);
-            if (!(fg->outputs[fg->nb_outputs - 1] = av_mallocz(sizeof(*fg->outputs[0]))))
-                exit_program(1);
-            fg->outputs[fg->nb_outputs - 1]->graph   = fg;
-            fg->outputs[fg->nb_outputs - 1]->out_tmp = cur;
-            cur = cur->next;
-            fg->outputs[fg->nb_outputs - 1]->out_tmp->next = NULL;
-        }
-    }
-
-    return 0;
-}
-
-static 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;
-}
-
 static void term_exit(void)
 {
     av_log(NULL, AV_LOG_QUIET, "");
diff --git a/avconv.h b/avconv.h
index fb720d6259..d8bf78b419 100644
--- a/avconv.h
+++ b/avconv.h
@@ -356,5 +356,7 @@ int guess_input_channel_layout(InputStream *ist);
 
 int configure_filtergraph(FilterGraph *fg);
 int configure_output_filter(FilterGraph *fg, OutputFilter *ofilter, AVFilterInOut *out);
+int ist_in_filtergraph(FilterGraph *fg, InputStream *ist);
+FilterGraph *init_simple_filtergraph(InputStream *ist, OutputStream *ost);
 
 #endif /* AVCONV_H */
diff --git a/avconv_filter.c b/avconv_filter.c
new file mode 100644
index 0000000000..d0ab4dcaf8
--- /dev/null
+++ b/avconv_filter.c
@@ -0,0 +1,560 @@
+/*
+ * avconv filter configuration
+ *
+ * This file is part of Libav.
+ *
+ * Libav 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.
+ *
+ * Libav 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 Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "avconv.h"
+
+#include "libavfilter/avfilter.h"
+#include "libavfilter/avfiltergraph.h"
+
+#include "libavutil/audioconvert.h"
+#include "libavutil/avassert.h"
+#include "libavutil/pixdesc.h"
+#include "libavutil/pixfmt.h"
+#include "libavutil/samplefmt.h"
+
+/**
+ * Define a function for building a string containing a list of
+ * allowed formats,
+ */
+#define DEF_CHOOSE_FORMAT(type, var, supported_list, none, get_name, separator)\
+static char *choose_ ## var ## s(OutputStream *ost)                            \
+{                                                                              \
+    if (ost->st->codec->var != none) {                                         \
+        get_name(ost->st->codec->var);                                         \
+        return av_strdup(name);                                                \
+    } else if (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" separator, name);                              \
+        }                                                                      \
+        len = avio_close_dyn_buf(s, &ret);                                     \
+        ret[len - 1] = 0;                                                      \
+        return ret;                                                            \
+    } else                                                                     \
+        return NULL;                                                           \
+}
+
+#define GET_PIX_FMT_NAME(pix_fmt)\
+    const char *name = av_get_pix_fmt_name(pix_fmt);
+
+DEF_CHOOSE_FORMAT(enum PixelFormat, pix_fmt, pix_fmts, PIX_FMT_NONE,
+                  GET_PIX_FMT_NAME, ":")
+
+#define GET_SAMPLE_FMT_NAME(sample_fmt)\
+    const char *name = av_get_sample_fmt_name(sample_fmt)
+
+DEF_CHOOSE_FORMAT(enum AVSampleFormat, sample_fmt, sample_fmts,
+                  AV_SAMPLE_FMT_NONE, GET_SAMPLE_FMT_NAME, ",")
+
+#define GET_SAMPLE_RATE_NAME(rate)\
+    char name[16];\
+    snprintf(name, sizeof(name), "%d", rate);
+
+DEF_CHOOSE_FORMAT(int, sample_rate, supported_samplerates, 0,
+                  GET_SAMPLE_RATE_NAME, ",")
+
+#define GET_CH_LAYOUT_NAME(ch_layout)\
+    char name[16];\
+    snprintf(name, sizeof(name), "0x%"PRIx64, ch_layout);
+
+DEF_CHOOSE_FORMAT(uint64_t, channel_layout, channel_layouts, 0,
+                  GET_CH_LAYOUT_NAME, ",")
+
+FilterGraph *init_simple_filtergraph(InputStream *ist, OutputStream *ost)
+{
+    FilterGraph *fg = av_mallocz(sizeof(*fg));
+
+    if (!fg)
+        exit_program(1);
+    fg->index = nb_filtergraphs;
+
+    fg->outputs = grow_array(fg->outputs, sizeof(*fg->outputs), &fg->nb_outputs,
+                             fg->nb_outputs + 1);
+    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];
+
+    fg->inputs = grow_array(fg->inputs, sizeof(*fg->inputs), &fg->nb_inputs,
+                            fg->nb_inputs + 1);
+    if (!(fg->inputs[0] = av_mallocz(sizeof(*fg->inputs[0]))))
+        exit_program(1);
+    fg->inputs[0]->ist   = ist;
+    fg->inputs[0]->graph = fg;
+
+    ist->filters = grow_array(ist->filters, sizeof(*ist->filters),
+                              &ist->nb_filters, ist->nb_filters + 1);
+    ist->filters[ist->nb_filters - 1] = fg->inputs[0];
+
+    filtergraphs = grow_array(filtergraphs, sizeof(*filtergraphs),
+                              &nb_filtergraphs, nb_filtergraphs + 1);
+    filtergraphs[nb_filtergraphs - 1] = fg;
+
+    return fg;
+}
+
+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 filtegraph 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++) {
+            if (s->streams[i]->codec->codec_type != type)
+                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->st->codec->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", in->pad_idx,
+                   in->filter_ctx->name);
+            exit_program(1);
+        }
+    }
+    av_assert0(ist);
+
+    ist->discard         = 0;
+    ist->decoding_needed = 1;
+    ist->st->discard = AVDISCARD_NONE;
+
+    fg->inputs = grow_array(fg->inputs, sizeof(*fg->inputs),
+                            &fg->nb_inputs, fg->nb_inputs + 1);
+    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;
+
+    ist->filters = grow_array(ist->filters, sizeof(*ist->filters),
+                              &ist->nb_filters, ist->nb_filters + 1);
+    ist->filters[ist->nb_filters - 1] = fg->inputs[fg->nb_inputs - 1];
+}
+
+static int configure_output_video_filter(FilterGraph *fg, OutputFilter *ofilter, AVFilterInOut *out)
+{
+    char *pix_fmts;
+    OutputStream *ost = ofilter->ost;
+    AVCodecContext *codec = ost->st->codec;
+    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, pix_fmts, fg->graph);
+    if (ret < 0)
+        return ret;
+
+    if (codec->width || codec->height) {
+        char args[255];
+        AVFilterContext *filter;
+
+        snprintf(args, sizeof(args), "%d:%d:flags=0x%X",
+                 codec->width,
+                 codec->height,
+                 (unsigned)ost->sws_flags);
+        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);
+        if ((ret = avfilter_graph_create_filter(&filter,
+                                                avfilter_get_by_name("format"),
+                                                "format", pix_fmts, 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;
+        av_freep(&pix_fmts);
+    }
+
+    if (ost->frame_rate.num) {
+        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;
+    }
+
+    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;
+    AVCodecContext *codec  = ost->st->codec;
+    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 (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];
+        int len = 0;
+
+        if (sample_fmts)
+            len += snprintf(args + len, sizeof(args) - len, "sample_fmts=%s:",
+                            sample_fmts);
+        if (sample_rates)
+            len += snprintf(args + len, sizeof(args) - len, "sample_rates=%s:",
+                            sample_rates);
+        if (channel_layouts)
+            len += snprintf(args + len, sizeof(args) - len, "channel_layouts=%s:",
+                            channel_layouts);
+        args[len - 1] = 0;
+
+        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 ((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->input_count : ctx->output_count; \
+    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);
+
+    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 configure_input_video_filter(FilterGraph *fg, InputFilter *ifilter,
+                                        AVFilterInOut *in)
+{
+    AVFilterContext *first_filter = in->filter_ctx;
+    AVFilter *filter = avfilter_get_by_name("buffer");
+    InputStream *ist = ifilter->ist;
+    AVRational tb = ist->framerate.num ? av_inv_q(ist->framerate) :
+                                         ist->st->time_base;
+    AVRational sar;
+    char args[255], name[255];
+    int pad_idx = in->pad_idx;
+    int ret;
+
+    sar = ist->st->sample_aspect_ratio.num ?
+          ist->st->sample_aspect_ratio :
+          ist->st->codec->sample_aspect_ratio;
+    snprintf(args, sizeof(args), "%d:%d:%d:%d:%d:%d:%d", ist->st->codec->width,
+             ist->st->codec->height, ist->st->codec->pix_fmt,
+             tb.num, tb.den, sar.num, sar.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, filter, name,
+                                            args, NULL, fg->graph)) < 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(setpts, 0, first_filter, pad_idx)) < 0)
+            return ret;
+
+        first_filter = setpts;
+        pad_idx = 0;
+    }
+
+    if ((ret = avfilter_link(ifilter->filter, 0, first_filter, pad_idx)) < 0)
+        return ret;
+    return 0;
+}
+
+static int configure_input_audio_filter(FilterGraph *fg, InputFilter *ifilter,
+                                        AVFilterInOut *in)
+{
+    AVFilterContext *first_filter = in->filter_ctx;
+    AVFilter *filter = avfilter_get_by_name("abuffer");
+    InputStream *ist = ifilter->ist;
+    int pad_idx = in->pad_idx;
+    char args[255], name[255];
+    int ret;
+
+    snprintf(args, sizeof(args), "time_base=%d/%d:sample_rate=%d:sample_fmt=%s"
+             ":channel_layout=0x%"PRIx64,
+             1, ist->st->codec->sample_rate,
+             ist->st->codec->sample_rate,
+             av_get_sample_fmt_name(ist->st->codec->sample_fmt),
+             ist->st->codec->channel_layout);
+    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, filter,
+                                            name, args, NULL,
+                                            fg->graph)) < 0)
+        return ret;
+
+    if (audio_sync_method > 0) {
+        AVFilterContext *async;
+        char args[256];
+        int  len = 0;
+
+        av_log(NULL, AV_LOG_WARNING, "-async has been deprecated. Used the "
+               "asyncts audio filter instead.\n");
+
+        if (audio_sync_method > 1)
+            len += snprintf(args + len, sizeof(args) - len, "compensate=1:"
+                            "max_comp=%d:", audio_sync_method);
+        snprintf(args + len, sizeof(args) - len, "min_delta=%f",
+                 audio_drift_threshold);
+
+        snprintf(name, sizeof(name), "graph %d audio sync for input stream %d:%d",
+                 fg->index, ist->file_index, ist->st->index);
+        ret = avfilter_graph_create_filter(&async,
+                                           avfilter_get_by_name("asyncts"),
+                                           name, args, NULL, fg->graph);
+        if (ret < 0)
+            return ret;
+
+        ret = avfilter_link(async, 0, first_filter, pad_idx);
+        if (ret < 0)
+            return ret;
+
+        first_filter = async;
+        pad_idx = 0;
+    }
+    if ((ret = avfilter_link(ifilter->filter, 0, first_filter, 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);
+
+    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, init = !fg->graph, simple = !fg->graph_desc;
+    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[255];
+        snprintf(args, sizeof(args), "flags=0x%X", (unsigned)ost->sws_flags);
+        fg->graph->scale_sws_opts = av_strdup(args);
+    }
+
+    if ((ret = avfilter_graph_parse2(fg->graph, graph_desc, &inputs, &outputs)) < 0)
+        return ret;
+
+    if (simple && (!inputs || inputs->next || !outputs || outputs->next)) {
+        av_log(NULL, AV_LOG_ERROR, "Simple filtergraph '%s' does not have "
+               "exactly one input and output.\n", graph_desc);
+        return AVERROR(EINVAL);
+    }
+
+    for (cur = inputs; !simple && init && cur; cur = cur->next)
+        init_input_filter(fg, cur);
+
+    for (cur = inputs, i = 0; cur; cur = cur->next, i++)
+        if ((ret = configure_input_filter(fg, fg->inputs[i], cur)) < 0)
+            return ret;
+    avfilter_inout_free(&inputs);
+
+    if (!init || simple) {
+        /* we already know the mappings between lavfi outputs and output streams,
+         * so we can finish the setup */
+        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;
+    } else {
+        /* wait until output mappings are processed */
+        for (cur = outputs; cur;) {
+            fg->outputs = grow_array(fg->outputs, sizeof(*fg->outputs),
+                                     &fg->nb_outputs, fg->nb_outputs + 1);
+            if (!(fg->outputs[fg->nb_outputs - 1] = av_mallocz(sizeof(*fg->outputs[0]))))
+                exit_program(1);
+            fg->outputs[fg->nb_outputs - 1]->graph   = fg;
+            fg->outputs[fg->nb_outputs - 1]->out_tmp = cur;
+            cur = cur->next;
+            fg->outputs[fg->nb_outputs - 1]->out_tmp->next = NULL;
+        }
+    }
+
+    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;
+}
+