avconv: decouple configuring filtergraphs and setting output parameters

Currently, a filtergraph will pull in the output constraints from its
corresponding decoder context, which breaks proper layering. Instead,
explicitly send the constaints on the output parameters to the
filtergraph.

This is similar to what is done for filtergraph inputs in
30ab4c51a1

avconv.c

@@ -154,6 +154,9 @@ static void avconv_cleanup(int ret)
         av_freep(&fg->inputs);
         for (j = 0; j < fg->nb_outputs; j++) {
             av_freep(&fg->outputs[j]->name);
+            av_freep(&fg->outputs[j]->formats);
+            av_freep(&fg->outputs[j]->channel_layouts);
+            av_freep(&fg->outputs[j]->sample_rates);
             av_freep(&fg->outputs[j]);
         }
         av_freep(&fg->outputs);

avconv.h

@@ -221,6 +221,18 @@ typedef struct OutputFilter {
     /* temporary storage until stream maps are processed */
     AVFilterInOut       *out_tmp;
     enum AVMediaType     type;
+
+    /* desired output stream properties */
+    int width, height;
+    AVRational frame_rate;
+    int format;
+    int sample_rate;
+    uint64_t channel_layout;
+
+    // those are only set if no format is specified and the encoder gives us multiple options
+    int *formats;
+    uint64_t *channel_layouts;
+    int *sample_rates;
 } OutputFilter;
 
 typedef struct FilterGraph {

avconv_filter.c

@@ -38,13 +38,13 @@
 
 /* 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)                            \
+#define DEF_CHOOSE_FORMAT(suffix, type, var, supported_list, none, get_name)   \
+static char *choose_ ## suffix (OutputFilter *ofilter)                         \
 {                                                                              \
-    if (ost->enc_ctx->var != none) {                                           \
-        get_name(ost->enc_ctx->var);                                           \
+    if (ofilter->var != none) {                                                \
+        get_name(ofilter->var);                                                \
         return av_strdup(name);                                                \
-    } else if (ost->enc && ost->enc->supported_list) {                         \
+    } else if (ofilter->supported_list) {                                      \
         const type *p;                                                         \
         AVIOContext *s = NULL;                                                 \
         uint8_t *ret;                                                          \
@@ -53,7 +53,7 @@ static char *choose_ ## var ## s(OutputStream *ost)                            \
         if (avio_open_dyn_buf(&s) < 0)                                         \
             exit(1);                                                           \
                                                                                \
-        for (p = ost->enc->supported_list; *p != none; p++) {                  \
+        for (p = ofilter->supported_list; *p != none; p++) {                   \
             get_name(*p);                                                      \
             avio_printf(s, "%s|", name);                                       \
         }                                                                      \
@@ -64,16 +64,16 @@ static char *choose_ ## var ## s(OutputStream *ost)                            \
         return NULL;                                                           \
 }
 
-DEF_CHOOSE_FORMAT(enum AVPixelFormat, pix_fmt, pix_fmts, AV_PIX_FMT_NONE,
+DEF_CHOOSE_FORMAT(pix_fmts, enum AVPixelFormat, format, formats, AV_PIX_FMT_NONE,
                   GET_PIX_FMT_NAME)
 
-DEF_CHOOSE_FORMAT(enum AVSampleFormat, sample_fmt, sample_fmts,
+DEF_CHOOSE_FORMAT(sample_fmts, enum AVSampleFormat, format, formats,
                   AV_SAMPLE_FMT_NONE, GET_SAMPLE_FMT_NAME)
 
-DEF_CHOOSE_FORMAT(int, sample_rate, supported_samplerates, 0,
+DEF_CHOOSE_FORMAT(sample_rates, int, sample_rate, sample_rates, 0,
                   GET_SAMPLE_RATE_NAME)
 
-DEF_CHOOSE_FORMAT(uint64_t, channel_layout, channel_layouts, 0,
+DEF_CHOOSE_FORMAT(channel_layouts, uint64_t, channel_layout, channel_layouts, 0,
                   GET_CH_LAYOUT_NAME)
 
 int init_simple_filtergraph(InputStream *ist, OutputStream *ost)
@@ -89,6 +89,7 @@ int init_simple_filtergraph(InputStream *ist, OutputStream *ost)
         exit(1);
     fg->outputs[0]->ost   = ost;
     fg->outputs[0]->graph = fg;
+    fg->outputs[0]->format = -1;
 
     ost->filter = fg->outputs[0];
 
@@ -296,7 +297,6 @@ static int configure_output_video_filter(FilterGraph *fg, OutputFilter *ofilter,
     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;
@@ -309,13 +309,12 @@ static int configure_output_video_filter(FilterGraph *fg, OutputFilter *ofilter,
     if (ret < 0)
         return ret;
 
-    if (!hw_device_ctx && (codec->width || codec->height)) {
+    if (!hw_device_ctx && (ofilter->width || ofilter->height)) {
         char args[255];
         AVFilterContext *filter;
 
         snprintf(args, sizeof(args), "%d:%d:0x%X",
-                 codec->width,
-                 codec->height,
+                 ofilter->width, ofilter->height,
                  (unsigned)ost->sws_flags);
         snprintf(name, sizeof(name), "scaler for output stream %d:%d",
                  ost->file_index, ost->index);
@@ -329,7 +328,7 @@ static int configure_output_video_filter(FilterGraph *fg, OutputFilter *ofilter,
         pad_idx = 0;
     }
 
-    if ((pix_fmts = choose_pix_fmts(ost))) {
+    if ((pix_fmts = choose_pix_fmts(ofilter))) {
         AVFilterContext *filter;
         snprintf(name, sizeof(name), "pixel format for output stream %d:%d",
                  ost->file_index, ost->index);
@@ -402,9 +401,9 @@ static int configure_output_audio_filter(FilterGraph *fg, OutputFilter *ofilter,
     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);
+    sample_fmts     = choose_sample_fmts(ofilter);
+    sample_rates    = choose_sample_rates(ofilter);
+    channel_layouts = choose_channel_layouts(ofilter);
     if (sample_fmts || sample_rates || channel_layouts) {
         AVFilterContext *format;
         char args[256];
@@ -747,6 +746,21 @@ int configure_filtergraph(FilterGraph *fg)
     if ((ret = avfilter_graph_config(fg->graph, NULL)) < 0)
         return ret;
 
+    /* limit the lists of allowed formats to the ones selected, to
+     * make sure they stay the same if the filtergraph is reconfigured later */
+    for (i = 0; i < fg->nb_outputs; i++) {
+        OutputFilter *ofilter = fg->outputs[i];
+        AVFilterLink *link = ofilter->filter->inputs[0];
+
+        ofilter->format = link->format;
+
+        ofilter->width  = link->w;
+        ofilter->height = link->h;
+
+        ofilter->sample_rate    = link->sample_rate;
+        ofilter->channel_layout = link->channel_layout;
+    }
+
     return 0;
 }
 

avconv_opt.c

@@ -1473,6 +1473,7 @@ static void init_output_filter(OutputFilter *ofilter, OptionsContext *o,
     ost->filter       = ofilter;
 
     ofilter->ost      = ost;
+    ofilter->format   = -1;
 
     if (ost->stream_copy) {
         av_log(NULL, AV_LOG_ERROR, "Streamcopy requested for output stream %d:%d, "
@@ -1833,6 +1834,67 @@ loop_end:
             }
         }
 
+        /* set the filter output constraints */
+        if (ost->filter) {
+            OutputFilter *f = ost->filter;
+            int count;
+            switch (ost->enc_ctx->codec_type) {
+            case AVMEDIA_TYPE_VIDEO:
+                f->frame_rate = ost->frame_rate;
+                f->width      = ost->enc_ctx->width;
+                f->height     = ost->enc_ctx->height;
+                if (ost->enc_ctx->pix_fmt != AV_PIX_FMT_NONE) {
+                    f->format = ost->enc_ctx->pix_fmt;
+                } else if (ost->enc->pix_fmts) {
+                    count = 0;
+                    while (ost->enc->pix_fmts[count] != AV_PIX_FMT_NONE)
+                        count++;
+                    f->formats = av_mallocz_array(count + 1, sizeof(*f->formats));
+                    if (!f->formats)
+                        exit_program(1);
+                    memcpy(f->formats, ost->enc->pix_fmts, (count + 1) * sizeof(*f->formats));
+                }
+                break;
+            case AVMEDIA_TYPE_AUDIO:
+                if (ost->enc_ctx->sample_fmt != AV_SAMPLE_FMT_NONE) {
+                    f->format = ost->enc_ctx->sample_fmt;
+                } else if (ost->enc->sample_fmts) {
+                    count = 0;
+                    while (ost->enc->sample_fmts[count] != AV_SAMPLE_FMT_NONE)
+                        count++;
+                    f->formats = av_mallocz_array(count + 1, sizeof(*f->formats));
+                    if (!f->formats)
+                        exit_program(1);
+                    memcpy(f->formats, ost->enc->sample_fmts, (count + 1) * sizeof(*f->formats));
+                }
+                if (ost->enc_ctx->sample_rate) {
+                    f->sample_rate = ost->enc_ctx->sample_rate;
+                } else if (ost->enc->supported_samplerates) {
+                    count = 0;
+                    while (ost->enc->supported_samplerates[count])
+                        count++;
+                    f->sample_rates = av_mallocz_array(count + 1, sizeof(*f->sample_rates));
+                    if (!f->sample_rates)
+                        exit_program(1);
+                    memcpy(f->sample_rates, ost->enc->supported_samplerates,
+                           (count + 1) * sizeof(*f->sample_rates));
+                }
+                if (ost->enc_ctx->channels) {
+                    f->channel_layout = av_get_default_channel_layout(ost->enc_ctx->channels);
+                } else if (ost->enc->channel_layouts) {
+                    count = 0;
+                    while (ost->enc->channel_layouts[count])
+                        count++;
+                    f->channel_layouts = av_mallocz_array(count + 1, sizeof(*f->channel_layouts));
+                    if (!f->channel_layouts)
+                        exit_program(1);
+                    memcpy(f->channel_layouts, ost->enc->channel_layouts,
+                           (count + 1) * sizeof(*f->channel_layouts));
+                }
+                break;
+            }
+        }
+
     }
 
     /* check filename in case of an image number is expected */