lavfi: rename asrc_aevalsrc.c to aeval.c

The file now contains both source and filter, the new name looks more
appropriate.

1 files changed, 466 insertions, 0 deletions

diff --git a/libavfilter/aeval.c b/libavfilter/aeval.c
new file mode 100644
index 0000000000..3a05fb016e
--- /dev/null
+++ b/libavfilter/aeval.c
@@ -0,0 +1,466 @@
+/*
+ * Copyright (c) 2011 Stefano Sabatini
+ *
+ * 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
+ */
+
+/**
+ * @file
+ * eval audio source
+ */
+
+#include "libavutil/avassert.h"
+#include "libavutil/avstring.h"
+#include "libavutil/channel_layout.h"
+#include "libavutil/eval.h"
+#include "libavutil/opt.h"
+#include "libavutil/parseutils.h"
+#include "avfilter.h"
+#include "audio.h"
+#include "internal.h"
+
+static const char * const var_names[] = {
+    "ch",           ///< the value of the current channel
+    "n",            ///< number of frame
+    "nb_in_channels",
+    "nb_out_channels",
+    "t",            ///< timestamp expressed in seconds
+    "s",            ///< sample rate
+    NULL
+};
+
+enum var_name {
+    VAR_CH,
+    VAR_N,
+    VAR_NB_IN_CHANNELS,
+    VAR_NB_OUT_CHANNELS,
+    VAR_T,
+    VAR_S,
+    VAR_VARS_NB
+};
+
+typedef struct {
+    const AVClass *class;
+    char *sample_rate_str;
+    int sample_rate;
+    int64_t chlayout;
+    char *chlayout_str;
+    int nb_channels;            ///< number of output channels
+    int nb_in_channels;         ///< number of input channels
+    int same_chlayout;          ///< set output as input channel layout
+    int64_t pts;
+    AVExpr **expr;
+    char *exprs;
+    int nb_samples;             ///< number of samples per requested frame
+    int64_t duration;
+    uint64_t n;
+    double var_values[VAR_VARS_NB];
+    double *channel_values;
+    int64_t out_channel_layout;
+} EvalContext;
+
+static double val(void *priv, double ch)
+{
+    EvalContext *eval = priv;
+    return eval->channel_values[FFMIN((int)ch, eval->nb_in_channels-1)];
+}
+
+static double (* const aeval_func1[])(void *, double) = { val, NULL };
+static const char * const aeval_func1_names[] = { "val", NULL };
+
+#define OFFSET(x) offsetof(EvalContext, x)
+#define FLAGS AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
+
+static const AVOption aevalsrc_options[]= {
+    { "exprs",       "set the '|'-separated list of channels expressions", OFFSET(exprs), AV_OPT_TYPE_STRING, {.str = NULL}, .flags = FLAGS },
+    { "nb_samples",  "set the number of samples per requested frame", OFFSET(nb_samples),      AV_OPT_TYPE_INT,    {.i64 = 1024},    0,        INT_MAX, FLAGS },
+    { "n",           "set the number of samples per requested frame", OFFSET(nb_samples),      AV_OPT_TYPE_INT,    {.i64 = 1024},    0,        INT_MAX, FLAGS },
+    { "sample_rate", "set the sample rate",                           OFFSET(sample_rate_str), AV_OPT_TYPE_STRING, {.str = "44100"}, CHAR_MIN, CHAR_MAX, FLAGS },
+    { "s",           "set the sample rate",                           OFFSET(sample_rate_str), AV_OPT_TYPE_STRING, {.str = "44100"}, CHAR_MIN, CHAR_MAX, FLAGS },
+    { "duration",    "set audio duration", OFFSET(duration), AV_OPT_TYPE_DURATION, {.i64 = -1}, -1, INT64_MAX, FLAGS },
+    { "d",           "set audio duration", OFFSET(duration), AV_OPT_TYPE_DURATION, {.i64 = -1}, -1, INT64_MAX, FLAGS },
+    { "channel_layout", "set channel layout", OFFSET(chlayout_str), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, FLAGS },
+    { "c",              "set channel layout", OFFSET(chlayout_str), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, FLAGS },
+    { NULL }
+};
+
+AVFILTER_DEFINE_CLASS(aevalsrc);
+
+static int parse_channel_expressions(AVFilterContext *ctx,
+                                     int expected_nb_channels)
+{
+    EvalContext *eval = ctx->priv;
+    char *args1 = av_strdup(eval->exprs);
+    char *expr, *last_expr, *buf;
+    double (* const *func1)(void *, double) = NULL;
+    const char * const *func1_names = NULL;
+    int i, ret = 0;
+
+    if (!args1)
+        return AVERROR(ENOMEM);
+
+    if (!eval->exprs) {
+        av_log(ctx, AV_LOG_ERROR, "Channels expressions list is empty\n");
+        return AVERROR(EINVAL);
+    }
+
+    if (!strcmp(ctx->filter->name, "aeval")) {
+        func1 = aeval_func1;
+        func1_names = aeval_func1_names;
+    }
+
+#define ADD_EXPRESSION(expr_) do {                                      \
+        if (!av_dynarray2_add((void **)&eval->expr, &eval->nb_channels, \
+                              sizeof(*eval->expr), NULL)) {             \
+            ret = AVERROR(ENOMEM);                                      \
+            goto end;                                                   \
+        }                                                               \
+        eval->expr[eval->nb_channels-1] = NULL;                         \
+        ret = av_expr_parse(&eval->expr[eval->nb_channels - 1], expr_,  \
+                            var_names, func1_names, func1,              \
+                            NULL, NULL, 0, ctx);                        \
+        if (ret < 0)                                                    \
+            goto end;                                                   \
+    } while (0)
+
+    /* reset expressions */
+    for (i = 0; i < eval->nb_channels; i++) {
+        av_expr_free(eval->expr[i]);
+        eval->expr[i] = NULL;
+    }
+    av_freep(&eval->expr);
+    eval->nb_channels = 0;
+
+    buf = args1;
+    while (expr = av_strtok(buf, "|", &buf)) {
+        ADD_EXPRESSION(expr);
+        last_expr = expr;
+    }
+
+    if (expected_nb_channels > eval->nb_channels)
+        for (i = eval->nb_channels; i < expected_nb_channels; i++)
+            ADD_EXPRESSION(last_expr);
+
+    if (expected_nb_channels > 0 && eval->nb_channels != expected_nb_channels) {
+        av_log(ctx, AV_LOG_ERROR,
+               "Mismatch between the specified number of channel expressions '%d' "
+               "and the number of expected output channels '%d' for the specified channel layout\n",
+               eval->nb_channels, expected_nb_channels);
+        ret = AVERROR(EINVAL);
+        goto end;
+    }
+
+end:
+    av_free(args1);
+    return ret;
+}
+
+static av_cold int init(AVFilterContext *ctx)
+{
+    EvalContext *eval = ctx->priv;
+    int ret;
+
+    if (eval->chlayout_str) {
+        if (!strcmp(eval->chlayout_str, "same") && !strcmp(ctx->filter->name, "aeval")) {
+            eval->same_chlayout = 1;
+        } else {
+            ret = ff_parse_channel_layout(&eval->chlayout, NULL, eval->chlayout_str, ctx);
+            if (ret < 0)
+                return ret;
+
+            ret = parse_channel_expressions(ctx, av_get_channel_layout_nb_channels(eval->chlayout));
+            if (ret < 0)
+                return ret;
+        }
+    } else {
+        /* guess channel layout from nb expressions/channels */
+        if ((ret = parse_channel_expressions(ctx, -1)) < 0)
+            return ret;
+
+        eval->chlayout = av_get_default_channel_layout(eval->nb_channels);
+        if (!eval->chlayout && eval->nb_channels <= 0) {
+            av_log(ctx, AV_LOG_ERROR, "Invalid number of channels '%d' provided\n",
+                   eval->nb_channels);
+            return AVERROR(EINVAL);
+        }
+    }
+
+    if (eval->sample_rate_str)
+        if ((ret = ff_parse_sample_rate(&eval->sample_rate, eval->sample_rate_str, ctx)))
+            return ret;
+    eval->n = 0;
+
+    return ret;
+}
+
+static av_cold void uninit(AVFilterContext *ctx)
+{
+    EvalContext *eval = ctx->priv;
+    int i;
+
+    for (i = 0; i < eval->nb_channels; i++) {
+        av_expr_free(eval->expr[i]);
+        eval->expr[i] = NULL;
+    }
+    av_freep(&eval->expr);
+}
+
+static int config_props(AVFilterLink *outlink)
+{
+    EvalContext *eval = outlink->src->priv;
+    char buf[128];
+
+    outlink->time_base = (AVRational){1, eval->sample_rate};
+    outlink->sample_rate = eval->sample_rate;
+
+    eval->var_values[VAR_S] = eval->sample_rate;
+    eval->var_values[VAR_NB_IN_CHANNELS] = NAN;
+    eval->var_values[VAR_NB_OUT_CHANNELS] = outlink->channels;
+
+    av_get_channel_layout_string(buf, sizeof(buf), 0, eval->chlayout);
+
+    av_log(outlink->src, AV_LOG_VERBOSE,
+           "sample_rate:%d chlayout:%s duration:%"PRId64"\n",
+           eval->sample_rate, buf, eval->duration);
+
+    return 0;
+}
+
+static int query_formats(AVFilterContext *ctx)
+{
+    EvalContext *eval = ctx->priv;
+    static const enum AVSampleFormat sample_fmts[] = { AV_SAMPLE_FMT_DBLP, AV_SAMPLE_FMT_NONE };
+    int64_t chlayouts[] = { eval->chlayout ? eval->chlayout : FF_COUNT2LAYOUT(eval->nb_channels) , -1 };
+    int sample_rates[] = { eval->sample_rate, -1 };
+
+    ff_set_common_formats (ctx, ff_make_format_list(sample_fmts));
+    ff_set_common_channel_layouts(ctx, avfilter_make_format64_list(chlayouts));
+    ff_set_common_samplerates(ctx, ff_make_format_list(sample_rates));
+
+    return 0;
+}
+
+static int request_frame(AVFilterLink *outlink)
+{
+    EvalContext *eval = outlink->src->priv;
+    AVFrame *samplesref;
+    int i, j;
+    int64_t t = av_rescale(eval->n, AV_TIME_BASE, eval->sample_rate);
+
+    if (eval->duration >= 0 && t >= eval->duration)
+        return AVERROR_EOF;
+
+    samplesref = ff_get_audio_buffer(outlink, eval->nb_samples);
+    if (!samplesref)
+        return AVERROR(ENOMEM);
+
+    /* evaluate expression for each single sample and for each channel */
+    for (i = 0; i < eval->nb_samples; i++, eval->n++) {
+        eval->var_values[VAR_N] = eval->n;
+        eval->var_values[VAR_T] = eval->var_values[VAR_N] * (double)1/eval->sample_rate;
+
+        for (j = 0; j < eval->nb_channels; j++) {
+            *((double *) samplesref->extended_data[j] + i) =
+                av_expr_eval(eval->expr[j], eval->var_values, NULL);
+        }
+    }
+
+    samplesref->pts = eval->pts;
+    samplesref->sample_rate = eval->sample_rate;
+    eval->pts += eval->nb_samples;
+
+    return ff_filter_frame(outlink, samplesref);
+}
+
+#if CONFIG_AEVALSRC_FILTER
+static const AVFilterPad aevalsrc_outputs[] = {
+    {
+        .name          = "default",
+        .type          = AVMEDIA_TYPE_AUDIO,
+        .config_props  = config_props,
+        .request_frame = request_frame,
+    },
+    { NULL }
+};
+
+AVFilter ff_asrc_aevalsrc = {
+    .name          = "aevalsrc",
+    .description   = NULL_IF_CONFIG_SMALL("Generate an audio signal generated by an expression."),
+    .query_formats = query_formats,
+    .init          = init,
+    .uninit        = uninit,
+    .priv_size     = sizeof(EvalContext),
+    .inputs        = NULL,
+    .outputs       = aevalsrc_outputs,
+    .priv_class    = &aevalsrc_class,
+};
+
+#endif /* CONFIG_AEVALSRC_FILTER */
+
+#define OFFSET(x) offsetof(EvalContext, x)
+#define FLAGS AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
+
+static const AVOption aeval_options[]= {
+    { "exprs", "set the '|'-separated list of channels expressions", OFFSET(exprs), AV_OPT_TYPE_STRING, {.str = NULL}, .flags = FLAGS },
+    { "channel_layout", "set channel layout", OFFSET(chlayout_str), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, FLAGS },
+    { "c",              "set channel layout", OFFSET(chlayout_str), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, FLAGS },
+    { NULL }
+};
+
+AVFILTER_DEFINE_CLASS(aeval);
+
+static int aeval_query_formats(AVFilterContext *ctx)
+{
+    AVFilterFormats *formats = NULL;
+    AVFilterChannelLayouts *layouts;
+    AVFilterLink *inlink  = ctx->inputs[0];
+    AVFilterLink *outlink  = ctx->outputs[0];
+    EvalContext *eval = ctx->priv;
+    static const enum AVSampleFormat sample_fmts[] = {
+        AV_SAMPLE_FMT_DBLP, AV_SAMPLE_FMT_NONE
+    };
+
+    // inlink supports any channel layout
+    layouts = ff_all_channel_counts();
+    ff_channel_layouts_ref(layouts, &inlink->out_channel_layouts);
+
+    if (eval->same_chlayout) {
+        layouts = ff_all_channel_counts();
+        if (!layouts)
+            return AVERROR(ENOMEM);
+            ff_set_common_channel_layouts(ctx, layouts);
+    } else {
+        // outlink supports only requested output channel layout
+        layouts = NULL;
+        ff_add_channel_layout(&layouts,
+                              eval->out_channel_layout ? eval->out_channel_layout :
+                              FF_COUNT2LAYOUT(eval->nb_channels));
+        ff_channel_layouts_ref(layouts, &outlink->in_channel_layouts);
+    }
+
+    formats = ff_make_format_list(sample_fmts);
+    if (!formats)
+        return AVERROR(ENOMEM);
+    ff_set_common_formats(ctx, formats);
+
+    formats = ff_all_samplerates();
+    if (!formats)
+        return AVERROR(ENOMEM);
+    ff_set_common_samplerates(ctx, formats);
+
+    return 0;
+}
+
+static int aeval_config_output(AVFilterLink *outlink)
+{
+    AVFilterContext *ctx = outlink->src;
+    EvalContext *eval = ctx->priv;
+    AVFilterLink *inlink = ctx->inputs[0];
+    int ret;
+
+    if (eval->same_chlayout) {
+        eval->chlayout = inlink->channel_layout;
+
+        if ((ret = parse_channel_expressions(ctx, inlink->channels)) < 0)
+            return ret;
+    }
+
+    eval->n = 0;
+    eval->nb_in_channels = eval->var_values[VAR_NB_IN_CHANNELS] = inlink->channels;
+    eval->var_values[VAR_NB_OUT_CHANNELS] = outlink->channels;
+    eval->var_values[VAR_S] = inlink->sample_rate;
+    eval->var_values[VAR_T] = NAN;
+
+    eval->channel_values = av_realloc_f(eval->channel_values,
+                                        inlink->channels, sizeof(*eval->channel_values));
+    if (!eval->channel_values)
+        return AVERROR(ENOMEM);
+
+    return 0;
+}
+
+#define TS2T(ts, tb) ((ts) == AV_NOPTS_VALUE ? NAN : (double)(ts)*av_q2d(tb))
+
+static int filter_frame(AVFilterLink *inlink, AVFrame *in)
+{
+    EvalContext *eval     = inlink->dst->priv;
+    AVFilterLink *outlink = inlink->dst->outputs[0];
+    int nb_samples        = in->nb_samples;
+    AVFrame *out;
+    double t0;
+    int i, j;
+
+    /* do volume scaling in-place if input buffer is writable */
+    out = ff_get_audio_buffer(outlink, nb_samples);
+    if (!out)
+        return AVERROR(ENOMEM);
+    av_frame_copy_props(out, in);
+
+    t0 = TS2T(in->pts, inlink->time_base);
+
+    /* evaluate expression for each single sample and for each channel */
+    for (i = 0; i < nb_samples; i++, eval->n++) {
+        eval->var_values[VAR_N] = eval->n;
+        eval->var_values[VAR_T] = t0 + i * (double)1/inlink->sample_rate;
+
+        for (j = 0; j < inlink->channels; j++)
+            eval->channel_values[j] = *((double *) in->extended_data[j] + i);
+
+        for (j = 0; j < outlink->channels; j++) {
+            eval->var_values[VAR_CH] = j;
+            *((double *) out->extended_data[j] + i) =
+                av_expr_eval(eval->expr[j], eval->var_values, eval);
+        }
+    }
+
+    av_frame_free(&in);
+    return ff_filter_frame(outlink, out);
+}
+
+#if CONFIG_AEVAL_FILTER
+
+static const AVFilterPad aeval_inputs[] = {
+    {
+        .name           = "default",
+        .type           = AVMEDIA_TYPE_AUDIO,
+        .filter_frame   = filter_frame,
+    },
+    { NULL }
+};
+
+static const AVFilterPad aeval_outputs[] = {
+    {
+        .name          = "default",
+        .type          = AVMEDIA_TYPE_AUDIO,
+        .config_props  = aeval_config_output,
+    },
+    { NULL }
+};
+
+AVFilter ff_af_aeval = {
+    .name          = "aeval",
+    .description   = NULL_IF_CONFIG_SMALL("Filter audio signal according to a specified expression."),
+    .query_formats = aeval_query_formats,
+    .init          = init,
+    .uninit        = uninit,
+    .priv_size     = sizeof(EvalContext),
+    .inputs        = aeval_inputs,
+    .outputs       = aeval_outputs,
+    .priv_class    = &aeval_class,
+};
+
+#endif /* CONFIG_AEVAL_FILTER */