diff options
Diffstat (limited to 'ffmpeg1/libavfilter/graphparser.c')
| -rw-r--r-- | ffmpeg1/libavfilter/graphparser.c | 601 |
1 files changed, 601 insertions, 0 deletions
diff --git a/ffmpeg1/libavfilter/graphparser.c b/ffmpeg1/libavfilter/graphparser.c new file mode 100644 index 0000000..8d2fffc --- /dev/null +++ b/ffmpeg1/libavfilter/graphparser.c @@ -0,0 +1,601 @@ +/* + * filter graph parser + * Copyright (c) 2008 Vitor Sessak + * Copyright (c) 2007 Bobby Bingham + * + * This file is part of FFmpeg. + * + * FFmpeg is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * FFmpeg is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with FFmpeg; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#include <string.h> +#include <stdio.h> + +#include "libavutil/avstring.h" +#include "libavutil/mem.h" +#include "avfilter.h" +#include "avfiltergraph.h" + +#define WHITESPACES " \n\t" + +/** + * Link two filters together. + * + * @see avfilter_link() + */ +static int link_filter(AVFilterContext *src, int srcpad, + AVFilterContext *dst, int dstpad, + void *log_ctx) +{ + int ret; + if ((ret = avfilter_link(src, srcpad, dst, dstpad))) { + av_log(log_ctx, AV_LOG_ERROR, + "Cannot create the link %s:%d -> %s:%d\n", + src->filter->name, srcpad, dst->filter->name, dstpad); + return ret; + } + + return 0; +} + +/** + * Parse the name of a link, which has the format "[linkname]". + * + * @return a pointer (that need to be freed after use) to the name + * between parenthesis + */ +static char *parse_link_name(const char **buf, void *log_ctx) +{ + const char *start = *buf; + char *name; + (*buf)++; + + name = av_get_token(buf, "]"); + + if (!name[0]) { + av_log(log_ctx, AV_LOG_ERROR, + "Bad (empty?) label found in the following: \"%s\".\n", start); + goto fail; + } + + if (*(*buf)++ != ']') { + av_log(log_ctx, AV_LOG_ERROR, + "Mismatched '[' found in the following: \"%s\".\n", start); + fail: + av_freep(&name); + } + + return name; +} + +/** + * Create an instance of a filter, initialize and insert it in the + * filtergraph in *ctx. + * + * @param filt_ctx put here a filter context in case of successful creation and configuration, NULL otherwise. + * @param ctx the filtergraph context + * @param index an index which is supposed to be unique for each filter instance added to the filtergraph + * @param filt_name the name of the filter to create + * @param args the arguments provided to the filter during its initialization + * @param log_ctx the log context to use + * @return 0 in case of success, a negative AVERROR code otherwise + */ +static int create_filter(AVFilterContext **filt_ctx, AVFilterGraph *ctx, int index, + const char *filt_name, const char *args, void *log_ctx) +{ + AVFilter *filt; + char inst_name[30]; + char tmp_args[256]; + int ret; + + snprintf(inst_name, sizeof(inst_name), "Parsed_%s_%d", filt_name, index); + + filt = avfilter_get_by_name(filt_name); + + if (!filt) { + av_log(log_ctx, AV_LOG_ERROR, + "No such filter: '%s'\n", filt_name); + return AVERROR(EINVAL); + } + + ret = avfilter_open(filt_ctx, filt, inst_name); + if (!*filt_ctx) { + av_log(log_ctx, AV_LOG_ERROR, + "Error creating filter '%s'\n", filt_name); + return ret; + } + + if ((ret = avfilter_graph_add_filter(ctx, *filt_ctx)) < 0) { + avfilter_free(*filt_ctx); + return ret; + } + + if (!strcmp(filt_name, "scale") && args && !strstr(args, "flags") + && ctx->scale_sws_opts) { + snprintf(tmp_args, sizeof(tmp_args), "%s:%s", + args, ctx->scale_sws_opts); + args = tmp_args; + } + + if ((ret = avfilter_init_filter(*filt_ctx, args, NULL)) < 0) { + av_log(log_ctx, AV_LOG_ERROR, + "Error initializing filter '%s' with args '%s'\n", filt_name, args); + return ret; + } + + return 0; +} + +/** + * Parse a string of the form FILTER_NAME[=PARAMS], and create a + * corresponding filter instance which is added to graph with + * create_filter(). + * + * @param filt_ctx Pointer that is set to the created and configured filter + * context on success, set to NULL on failure. + * @param filt_ctx put here a pointer to the created filter context on + * success, NULL otherwise + * @param buf pointer to the buffer to parse, *buf will be updated to + * point to the char next after the parsed string + * @param index an index which is assigned to the created filter + * instance, and which is supposed to be unique for each filter + * instance added to the filtergraph + * @return 0 in case of success, a negative AVERROR code otherwise + */ +static int parse_filter(AVFilterContext **filt_ctx, const char **buf, AVFilterGraph *graph, + int index, void *log_ctx) +{ + char *opts = NULL; + char *name = av_get_token(buf, "=,;[\n"); + int ret; + + if (**buf == '=') { + (*buf)++; + opts = av_get_token(buf, "[],;\n"); + } + + ret = create_filter(filt_ctx, graph, index, name, opts, log_ctx); + av_free(name); + av_free(opts); + return ret; +} + +AVFilterInOut *avfilter_inout_alloc(void) +{ + return av_mallocz(sizeof(AVFilterInOut)); +} + +void avfilter_inout_free(AVFilterInOut **inout) +{ + while (*inout) { + AVFilterInOut *next = (*inout)->next; + av_freep(&(*inout)->name); + av_freep(inout); + *inout = next; + } +} + +static AVFilterInOut *extract_inout(const char *label, AVFilterInOut **links) +{ + AVFilterInOut *ret; + + while (*links && (!(*links)->name || strcmp((*links)->name, label))) + links = &((*links)->next); + + ret = *links; + + if (ret) { + *links = ret->next; + ret->next = NULL; + } + + return ret; +} + +static void insert_inout(AVFilterInOut **inouts, AVFilterInOut *element) +{ + element->next = *inouts; + *inouts = element; +} + +static void append_inout(AVFilterInOut **inouts, AVFilterInOut **element) +{ + while (*inouts && (*inouts)->next) + inouts = &((*inouts)->next); + + if (!*inouts) + *inouts = *element; + else + (*inouts)->next = *element; + *element = NULL; +} + +static int link_filter_inouts(AVFilterContext *filt_ctx, + AVFilterInOut **curr_inputs, + AVFilterInOut **open_inputs, void *log_ctx) +{ + int pad, ret; + + for (pad = 0; pad < filt_ctx->nb_inputs; pad++) { + AVFilterInOut *p = *curr_inputs; + + if (p) { + *curr_inputs = (*curr_inputs)->next; + p->next = NULL; + } else if (!(p = av_mallocz(sizeof(*p)))) + return AVERROR(ENOMEM); + + if (p->filter_ctx) { + ret = link_filter(p->filter_ctx, p->pad_idx, filt_ctx, pad, log_ctx); + av_free(p->name); + av_free(p); + if (ret < 0) + return ret; + } else { + p->filter_ctx = filt_ctx; + p->pad_idx = pad; + append_inout(open_inputs, &p); + } + } + + if (*curr_inputs) { + av_log(log_ctx, AV_LOG_ERROR, + "Too many inputs specified for the \"%s\" filter.\n", + filt_ctx->filter->name); + return AVERROR(EINVAL); + } + + pad = filt_ctx->nb_outputs; + while (pad--) { + AVFilterInOut *currlinkn = av_mallocz(sizeof(AVFilterInOut)); + if (!currlinkn) + return AVERROR(ENOMEM); + currlinkn->filter_ctx = filt_ctx; + currlinkn->pad_idx = pad; + insert_inout(curr_inputs, currlinkn); + } + + return 0; +} + +static int parse_inputs(const char **buf, AVFilterInOut **curr_inputs, + AVFilterInOut **open_outputs, void *log_ctx) +{ + AVFilterInOut *parsed_inputs = NULL; + int pad = 0; + + while (**buf == '[') { + char *name = parse_link_name(buf, log_ctx); + AVFilterInOut *match; + + if (!name) + return AVERROR(EINVAL); + + /* First check if the label is not in the open_outputs list */ + match = extract_inout(name, open_outputs); + + if (match) { + av_free(name); + } else { + /* Not in the list, so add it as an input */ + if (!(match = av_mallocz(sizeof(AVFilterInOut)))) { + av_free(name); + return AVERROR(ENOMEM); + } + match->name = name; + match->pad_idx = pad; + } + + append_inout(&parsed_inputs, &match); + + *buf += strspn(*buf, WHITESPACES); + pad++; + } + + append_inout(&parsed_inputs, curr_inputs); + *curr_inputs = parsed_inputs; + + return pad; +} + +static int parse_outputs(const char **buf, AVFilterInOut **curr_inputs, + AVFilterInOut **open_inputs, + AVFilterInOut **open_outputs, void *log_ctx) +{ + int ret, pad = 0; + + while (**buf == '[') { + char *name = parse_link_name(buf, log_ctx); + AVFilterInOut *match; + + AVFilterInOut *input = *curr_inputs; + + if (!name) + return AVERROR(EINVAL); + + if (!input) { + av_log(log_ctx, AV_LOG_ERROR, + "No output pad can be associated to link label '%s'.\n", name); + av_free(name); + return AVERROR(EINVAL); + } + *curr_inputs = (*curr_inputs)->next; + + /* First check if the label is not in the open_inputs list */ + match = extract_inout(name, open_inputs); + + if (match) { + if ((ret = link_filter(input->filter_ctx, input->pad_idx, + match->filter_ctx, match->pad_idx, log_ctx)) < 0) { + av_free(name); + return ret; + } + av_free(match->name); + av_free(name); + av_free(match); + av_free(input); + } else { + /* Not in the list, so add the first input as a open_output */ + input->name = name; + insert_inout(open_outputs, input); + } + *buf += strspn(*buf, WHITESPACES); + pad++; + } + + return pad; +} + +static int parse_sws_flags(const char **buf, AVFilterGraph *graph) +{ + char *p = strchr(*buf, ';'); + + if (strncmp(*buf, "sws_flags=", 10)) + return 0; + + if (!p) { + av_log(graph, AV_LOG_ERROR, "sws_flags not terminated with ';'.\n"); + return AVERROR(EINVAL); + } + + *buf += 4; // keep the 'flags=' part + + av_freep(&graph->scale_sws_opts); + if (!(graph->scale_sws_opts = av_mallocz(p - *buf + 1))) + return AVERROR(ENOMEM); + av_strlcpy(graph->scale_sws_opts, *buf, p - *buf + 1); + + *buf = p + 1; + return 0; +} + +int avfilter_graph_parse2(AVFilterGraph *graph, const char *filters, + AVFilterInOut **inputs, + AVFilterInOut **outputs) +{ + int index = 0, ret = 0; + char chr = 0; + + AVFilterInOut *curr_inputs = NULL, *open_inputs = NULL, *open_outputs = NULL; + + filters += strspn(filters, WHITESPACES); + + if ((ret = parse_sws_flags(&filters, graph)) < 0) + goto fail; + + do { + AVFilterContext *filter; + filters += strspn(filters, WHITESPACES); + + if ((ret = parse_inputs(&filters, &curr_inputs, &open_outputs, graph)) < 0) + goto end; + if ((ret = parse_filter(&filter, &filters, graph, index, graph)) < 0) + goto end; + + + if ((ret = link_filter_inouts(filter, &curr_inputs, &open_inputs, graph)) < 0) + goto end; + + if ((ret = parse_outputs(&filters, &curr_inputs, &open_inputs, &open_outputs, + graph)) < 0) + goto end; + + filters += strspn(filters, WHITESPACES); + chr = *filters++; + + if (chr == ';' && curr_inputs) + append_inout(&open_outputs, &curr_inputs); + index++; + } while (chr == ',' || chr == ';'); + + if (chr) { + av_log(graph, AV_LOG_ERROR, + "Unable to parse graph description substring: \"%s\"\n", + filters - 1); + ret = AVERROR(EINVAL); + goto end; + } + + append_inout(&open_outputs, &curr_inputs); + + + *inputs = open_inputs; + *outputs = open_outputs; + return 0; + + fail:end: + for (; graph->nb_filters > 0; graph->nb_filters--) + avfilter_free(graph->filters[graph->nb_filters - 1]); + av_freep(&graph->filters); + avfilter_inout_free(&open_inputs); + avfilter_inout_free(&open_outputs); + avfilter_inout_free(&curr_inputs); + + *inputs = NULL; + *outputs = NULL; + + return ret; +} + +int avfilter_graph_parse(AVFilterGraph *graph, const char *filters, + AVFilterInOut **open_inputs_ptr, AVFilterInOut **open_outputs_ptr, + void *log_ctx) +{ +#if 0 + int ret; + AVFilterInOut *open_inputs = open_inputs_ptr ? *open_inputs_ptr : NULL; + AVFilterInOut *open_outputs = open_outputs_ptr ? *open_outputs_ptr : NULL; + AVFilterInOut *cur, *match, *inputs = NULL, *outputs = NULL; + + if ((ret = avfilter_graph_parse2(graph, filters, &inputs, &outputs)) < 0) + goto fail; + + /* First input can be omitted if it is "[in]" */ + if (inputs && !inputs->name) + inputs->name = av_strdup("in"); + for (cur = inputs; cur; cur = cur->next) { + if (!cur->name) { + av_log(log_ctx, AV_LOG_ERROR, + "Not enough inputs specified for the \"%s\" filter.\n", + cur->filter_ctx->filter->name); + ret = AVERROR(EINVAL); + goto fail; + } + if (!(match = extract_inout(cur->name, &open_outputs))) + continue; + ret = avfilter_link(match->filter_ctx, match->pad_idx, + cur->filter_ctx, cur->pad_idx); + avfilter_inout_free(&match); + if (ret < 0) + goto fail; + } + + /* Last output can be omitted if it is "[out]" */ + if (outputs && !outputs->name) + outputs->name = av_strdup("out"); + for (cur = outputs; cur; cur = cur->next) { + if (!cur->name) { + av_log(log_ctx, AV_LOG_ERROR, + "Invalid filterchain containing an unlabelled output pad: \"%s\"\n", + filters); + ret = AVERROR(EINVAL); + goto fail; + } + if (!(match = extract_inout(cur->name, &open_inputs))) + continue; + ret = avfilter_link(cur->filter_ctx, cur->pad_idx, + match->filter_ctx, match->pad_idx); + avfilter_inout_free(&match); + if (ret < 0) + goto fail; + } + + fail: + if (ret < 0) { + for (; graph->nb_filters > 0; graph->nb_filters--) + avfilter_free(graph->filters[graph->nb_filters - 1]); + av_freep(&graph->filters); + } + avfilter_inout_free(&inputs); + avfilter_inout_free(&outputs); + /* clear open_in/outputs only if not passed as parameters */ + if (open_inputs_ptr) *open_inputs_ptr = open_inputs; + else avfilter_inout_free(&open_inputs); + if (open_outputs_ptr) *open_outputs_ptr = open_outputs; + else avfilter_inout_free(&open_outputs); + return ret; +} +#else + int index = 0, ret = 0; + char chr = 0; + + AVFilterInOut *curr_inputs = NULL; + AVFilterInOut *open_inputs = open_inputs_ptr ? *open_inputs_ptr : NULL; + AVFilterInOut *open_outputs = open_outputs_ptr ? *open_outputs_ptr : NULL; + + if ((ret = parse_sws_flags(&filters, graph)) < 0) + goto end; + + do { + AVFilterContext *filter; + const char *filterchain = filters; + filters += strspn(filters, WHITESPACES); + + if ((ret = parse_inputs(&filters, &curr_inputs, &open_outputs, log_ctx)) < 0) + goto end; + + if ((ret = parse_filter(&filter, &filters, graph, index, log_ctx)) < 0) + goto end; + + if (filter->input_count == 1 && !curr_inputs && !index) { + /* First input pad, assume it is "[in]" if not specified */ + const char *tmp = "[in]"; + if ((ret = parse_inputs(&tmp, &curr_inputs, &open_outputs, log_ctx)) < 0) + goto end; + } + + if ((ret = link_filter_inouts(filter, &curr_inputs, &open_inputs, log_ctx)) < 0) + goto end; + + if ((ret = parse_outputs(&filters, &curr_inputs, &open_inputs, &open_outputs, + log_ctx)) < 0) + goto end; + + filters += strspn(filters, WHITESPACES); + chr = *filters++; + + if (chr == ';' && curr_inputs) { + av_log(log_ctx, AV_LOG_ERROR, + "Invalid filterchain containing an unlabelled output pad: \"%s\"\n", + filterchain); + ret = AVERROR(EINVAL); + goto end; + } + index++; + } while (chr == ',' || chr == ';'); + + if (chr) { + av_log(log_ctx, AV_LOG_ERROR, + "Unable to parse graph description substring: \"%s\"\n", + filters - 1); + ret = AVERROR(EINVAL); + goto end; + } + + if (curr_inputs) { + /* Last output pad, assume it is "[out]" if not specified */ + const char *tmp = "[out]"; + if ((ret = parse_outputs(&tmp, &curr_inputs, &open_inputs, &open_outputs, + log_ctx)) < 0) + goto end; + } + +end: + /* clear open_in/outputs only if not passed as parameters */ + if (open_inputs_ptr) *open_inputs_ptr = open_inputs; + else avfilter_inout_free(&open_inputs); + if (open_outputs_ptr) *open_outputs_ptr = open_outputs; + else avfilter_inout_free(&open_outputs); + avfilter_inout_free(&curr_inputs); + + if (ret < 0) { + for (; graph->nb_filters > 0; graph->nb_filters--) + avfilter_free(graph->filters[graph->nb_filters - 1]); + av_freep(&graph->filters); + } + return ret; +} + +#endif |