fftools/ffmpeg_opt: move opening input files to ffmpeg_demux.c

This is similar to what was done before for output files and will allow
introducing demuxer-private state in future commits

Unlike for muxing, the code is moved to existing ffmpeg_demux.c rather
than to a new file. The reason is just file size - the demuxing code is
much smaller than muxing.

1 files changed, 650 insertions, 0 deletions

diff --git a/fftools/ffmpeg_demux.c b/fftools/ffmpeg_demux.c
index 487053c592..946074c333 100644
--- a/fftools/ffmpeg_demux.c
+++ b/fftools/ffmpeg_demux.c
@@ -16,10 +16,19 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
+#include <float.h>
+#include <stdint.h>
+
 #include "ffmpeg.h"
 
 #include "libavutil/avassert.h"
+#include "libavutil/avstring.h"
+#include "libavutil/display.h"
 #include "libavutil/error.h"
+#include "libavutil/intreadwrite.h"
+#include "libavutil/opt.h"
+#include "libavutil/parseutils.h"
+#include "libavutil/pixdesc.h"
 #include "libavutil/time.h"
 #include "libavutil/timestamp.h"
 #include "libavutil/thread.h"
@@ -29,6 +38,20 @@
 
 #include "libavformat/avformat.h"
 
+static const char *const opt_name_discard[]                   = {"discard", NULL};
+static const char *const opt_name_reinit_filters[]            = {"reinit_filter", NULL};
+static const char *const opt_name_fix_sub_duration[]          = {"fix_sub_duration", NULL};
+static const char *const opt_name_canvas_sizes[]              = {"canvas_size", NULL};
+static const char *const opt_name_guess_layout_max[]          = {"guess_layout_max", NULL};
+static const char *const opt_name_ts_scale[]                  = {"itsscale", NULL};
+static const char *const opt_name_hwaccels[]                  = {"hwaccel", NULL};
+static const char *const opt_name_hwaccel_devices[]           = {"hwaccel_device", NULL};
+static const char *const opt_name_hwaccel_output_formats[]    = {"hwaccel_output_format", NULL};
+static const char *const opt_name_autorotate[]                = {"autorotate", NULL};
+static const char *const opt_name_display_rotations[]         = {"display_rotation", NULL};
+static const char *const opt_name_display_hflips[]            = {"display_hflip", NULL};
+static const char *const opt_name_display_vflips[]            = {"display_vflip", NULL};
+
 typedef struct DemuxMsg {
     AVPacket *pkt;
     int looping;
@@ -406,3 +429,630 @@ int ifile_get_packet(InputFile *f, AVPacket **pkt)
     *pkt = msg.pkt;
     return 0;
 }
+
+static const AVCodec *choose_decoder(OptionsContext *o, AVFormatContext *s, AVStream *st,
+                                     enum HWAccelID hwaccel_id, enum AVHWDeviceType hwaccel_device_type)
+
+{
+    char *codec_name = NULL;
+
+    MATCH_PER_STREAM_OPT(codec_names, str, codec_name, s, st);
+    if (codec_name) {
+        const AVCodec *codec = find_codec_or_die(codec_name, st->codecpar->codec_type, 0);
+        st->codecpar->codec_id = codec->id;
+        if (recast_media && st->codecpar->codec_type != codec->type)
+            st->codecpar->codec_type = codec->type;
+        return codec;
+    } else {
+        if (st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO &&
+            hwaccel_id == HWACCEL_GENERIC &&
+            hwaccel_device_type != AV_HWDEVICE_TYPE_NONE) {
+            const AVCodec *c;
+            void *i = NULL;
+
+            while ((c = av_codec_iterate(&i))) {
+                const AVCodecHWConfig *config;
+
+                if (c->id != st->codecpar->codec_id ||
+                    !av_codec_is_decoder(c))
+                    continue;
+
+                for (int j = 0; config = avcodec_get_hw_config(c, j); j++) {
+                    if (config->device_type == hwaccel_device_type) {
+                        av_log(NULL, AV_LOG_VERBOSE, "Selecting decoder '%s' because of requested hwaccel method %s\n",
+                               c->name, av_hwdevice_get_type_name(hwaccel_device_type));
+                        return c;
+                    }
+                }
+            }
+        }
+
+        return avcodec_find_decoder(st->codecpar->codec_id);
+    }
+}
+
+static int guess_input_channel_layout(InputStream *ist)
+{
+    AVCodecContext *dec = ist->dec_ctx;
+
+    if (dec->ch_layout.order == AV_CHANNEL_ORDER_UNSPEC) {
+        char layout_name[256];
+
+        if (dec->ch_layout.nb_channels > ist->guess_layout_max)
+            return 0;
+        av_channel_layout_default(&dec->ch_layout, dec->ch_layout.nb_channels);
+        if (dec->ch_layout.order == AV_CHANNEL_ORDER_UNSPEC)
+            return 0;
+        av_channel_layout_describe(&dec->ch_layout, layout_name, sizeof(layout_name));
+        av_log(NULL, AV_LOG_WARNING, "Guessed Channel Layout for Input Stream "
+               "#%d.%d : %s\n", ist->file_index, ist->st->index, layout_name);
+    }
+    return 1;
+}
+
+static void add_display_matrix_to_stream(OptionsContext *o,
+                                         AVFormatContext *ctx, AVStream *st)
+{
+    double rotation = DBL_MAX;
+    int hflip = -1, vflip = -1;
+    int hflip_set = 0, vflip_set = 0, rotation_set = 0;
+    int32_t *buf;
+
+    MATCH_PER_STREAM_OPT(display_rotations, dbl, rotation, ctx, st);
+    MATCH_PER_STREAM_OPT(display_hflips,    i,   hflip,    ctx, st);
+    MATCH_PER_STREAM_OPT(display_vflips,    i,   vflip,    ctx, st);
+
+    rotation_set = rotation != DBL_MAX;
+    hflip_set    = hflip != -1;
+    vflip_set    = vflip != -1;
+
+    if (!rotation_set && !hflip_set && !vflip_set)
+        return;
+
+    buf = (int32_t *)av_stream_new_side_data(st, AV_PKT_DATA_DISPLAYMATRIX, sizeof(int32_t) * 9);
+    if (!buf) {
+        av_log(NULL, AV_LOG_FATAL, "Failed to generate a display matrix!\n");
+        exit_program(1);
+    }
+
+    av_display_rotation_set(buf,
+                            rotation_set ? -(rotation) : -0.0f);
+
+    av_display_matrix_flip(buf,
+                           hflip_set ? hflip : 0,
+                           vflip_set ? vflip : 0);
+}
+
+/* Add all the streams from the given input file to the global
+ * list of input streams. */
+static void add_input_streams(OptionsContext *o, AVFormatContext *ic)
+{
+    int i, ret;
+
+    for (i = 0; i < ic->nb_streams; i++) {
+        AVStream *st = ic->streams[i];
+        AVCodecParameters *par = st->codecpar;
+        InputStream *ist;
+        char *framerate = NULL, *hwaccel_device = NULL;
+        const char *hwaccel = NULL;
+        char *hwaccel_output_format = NULL;
+        char *codec_tag = NULL;
+        char *next;
+        char *discard_str = NULL;
+        const AVClass *cc = avcodec_get_class();
+        const AVOption *discard_opt = av_opt_find(&cc, "skip_frame", NULL,
+                                                  0, AV_OPT_SEARCH_FAKE_OBJ);
+
+        ist = ALLOC_ARRAY_ELEM(input_streams, nb_input_streams);
+        ist->st = st;
+        ist->file_index = nb_input_files;
+        ist->discard = 1;
+        st->discard  = AVDISCARD_ALL;
+        ist->nb_samples = 0;
+        ist->first_dts = AV_NOPTS_VALUE;
+        ist->min_pts = INT64_MAX;
+        ist->max_pts = INT64_MIN;
+
+        ist->ts_scale = 1.0;
+        MATCH_PER_STREAM_OPT(ts_scale, dbl, ist->ts_scale, ic, st);
+
+        ist->autorotate = 1;
+        MATCH_PER_STREAM_OPT(autorotate, i, ist->autorotate, ic, st);
+
+        MATCH_PER_STREAM_OPT(codec_tags, str, codec_tag, ic, st);
+        if (codec_tag) {
+            uint32_t tag = strtol(codec_tag, &next, 0);
+            if (*next)
+                tag = AV_RL32(codec_tag);
+            st->codecpar->codec_tag = tag;
+        }
+
+        if (st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) {
+            add_display_matrix_to_stream(o, ic, st);
+
+            MATCH_PER_STREAM_OPT(hwaccels, str, hwaccel, ic, st);
+            MATCH_PER_STREAM_OPT(hwaccel_output_formats, str,
+                                 hwaccel_output_format, ic, st);
+
+            if (!hwaccel_output_format && hwaccel && !strcmp(hwaccel, "cuvid")) {
+                av_log(NULL, AV_LOG_WARNING,
+                    "WARNING: defaulting hwaccel_output_format to cuda for compatibility "
+                    "with old commandlines. This behaviour is DEPRECATED and will be removed "
+                    "in the future. Please explicitly set \"-hwaccel_output_format cuda\".\n");
+                ist->hwaccel_output_format = AV_PIX_FMT_CUDA;
+            } else if (!hwaccel_output_format && hwaccel && !strcmp(hwaccel, "qsv")) {
+                av_log(NULL, AV_LOG_WARNING,
+                    "WARNING: defaulting hwaccel_output_format to qsv for compatibility "
+                    "with old commandlines. This behaviour is DEPRECATED and will be removed "
+                    "in the future. Please explicitly set \"-hwaccel_output_format qsv\".\n");
+                ist->hwaccel_output_format = AV_PIX_FMT_QSV;
+            } else if (hwaccel_output_format) {
+                ist->hwaccel_output_format = av_get_pix_fmt(hwaccel_output_format);
+                if (ist->hwaccel_output_format == AV_PIX_FMT_NONE) {
+                    av_log(NULL, AV_LOG_FATAL, "Unrecognised hwaccel output "
+                           "format: %s", hwaccel_output_format);
+                }
+            } else {
+                ist->hwaccel_output_format = AV_PIX_FMT_NONE;
+            }
+
+            if (hwaccel) {
+                // The NVDEC hwaccels use a CUDA device, so remap the name here.
+                if (!strcmp(hwaccel, "nvdec") || !strcmp(hwaccel, "cuvid"))
+                    hwaccel = "cuda";
+
+                if (!strcmp(hwaccel, "none"))
+                    ist->hwaccel_id = HWACCEL_NONE;
+                else if (!strcmp(hwaccel, "auto"))
+                    ist->hwaccel_id = HWACCEL_AUTO;
+                else {
+                    enum AVHWDeviceType type = av_hwdevice_find_type_by_name(hwaccel);
+                    if (type != AV_HWDEVICE_TYPE_NONE) {
+                        ist->hwaccel_id = HWACCEL_GENERIC;
+                        ist->hwaccel_device_type = type;
+                    }
+
+                    if (!ist->hwaccel_id) {
+                        av_log(NULL, AV_LOG_FATAL, "Unrecognized hwaccel: %s.\n",
+                               hwaccel);
+                        av_log(NULL, AV_LOG_FATAL, "Supported hwaccels: ");
+                        type = AV_HWDEVICE_TYPE_NONE;
+                        while ((type = av_hwdevice_iterate_types(type)) !=
+                               AV_HWDEVICE_TYPE_NONE)
+                            av_log(NULL, AV_LOG_FATAL, "%s ",
+                                   av_hwdevice_get_type_name(type));
+                        av_log(NULL, AV_LOG_FATAL, "\n");
+                        exit_program(1);
+                    }
+                }
+            }
+
+            MATCH_PER_STREAM_OPT(hwaccel_devices, str, hwaccel_device, ic, st);
+            if (hwaccel_device) {
+                ist->hwaccel_device = av_strdup(hwaccel_device);
+                if (!ist->hwaccel_device)
+                    report_and_exit(AVERROR(ENOMEM));
+            }
+
+            ist->hwaccel_pix_fmt = AV_PIX_FMT_NONE;
+        }
+
+        ist->dec = choose_decoder(o, ic, st, ist->hwaccel_id, ist->hwaccel_device_type);
+        ist->decoder_opts = filter_codec_opts(o->g->codec_opts, ist->st->codecpar->codec_id, ic, st, ist->dec);
+
+        ist->reinit_filters = -1;
+        MATCH_PER_STREAM_OPT(reinit_filters, i, ist->reinit_filters, ic, st);
+
+        MATCH_PER_STREAM_OPT(discard, str, discard_str, ic, st);
+        ist->user_set_discard = AVDISCARD_NONE;
+
+        if ((o->video_disable && ist->st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) ||
+            (o->audio_disable && ist->st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO) ||
+            (o->subtitle_disable && ist->st->codecpar->codec_type == AVMEDIA_TYPE_SUBTITLE) ||
+            (o->data_disable && ist->st->codecpar->codec_type == AVMEDIA_TYPE_DATA))
+                ist->user_set_discard = AVDISCARD_ALL;
+
+        if (discard_str && av_opt_eval_int(&cc, discard_opt, discard_str, &ist->user_set_discard) < 0) {
+            av_log(NULL, AV_LOG_ERROR, "Error parsing discard %s.\n",
+                    discard_str);
+            exit_program(1);
+        }
+
+        ist->filter_in_rescale_delta_last = AV_NOPTS_VALUE;
+        ist->prev_pkt_pts = AV_NOPTS_VALUE;
+
+        ist->dec_ctx = avcodec_alloc_context3(ist->dec);
+        if (!ist->dec_ctx)
+            report_and_exit(AVERROR(ENOMEM));
+
+        ret = avcodec_parameters_to_context(ist->dec_ctx, par);
+        if (ret < 0) {
+            av_log(NULL, AV_LOG_ERROR, "Error initializing the decoder context.\n");
+            exit_program(1);
+        }
+
+        ist->decoded_frame = av_frame_alloc();
+        if (!ist->decoded_frame)
+            report_and_exit(AVERROR(ENOMEM));
+
+        ist->pkt = av_packet_alloc();
+        if (!ist->pkt)
+            report_and_exit(AVERROR(ENOMEM));
+
+        if (o->bitexact)
+            ist->dec_ctx->flags |= AV_CODEC_FLAG_BITEXACT;
+
+        switch (par->codec_type) {
+        case AVMEDIA_TYPE_VIDEO:
+            // avformat_find_stream_info() doesn't set this for us anymore.
+            ist->dec_ctx->framerate = st->avg_frame_rate;
+
+            MATCH_PER_STREAM_OPT(frame_rates, str, framerate, ic, st);
+            if (framerate && av_parse_video_rate(&ist->framerate,
+                                                 framerate) < 0) {
+                av_log(NULL, AV_LOG_ERROR, "Error parsing framerate %s.\n",
+                       framerate);
+                exit_program(1);
+            }
+
+            ist->top_field_first = -1;
+            MATCH_PER_STREAM_OPT(top_field_first, i, ist->top_field_first, ic, st);
+
+            ist->framerate_guessed = av_guess_frame_rate(ic, st, NULL);
+
+            break;
+        case AVMEDIA_TYPE_AUDIO:
+            ist->guess_layout_max = INT_MAX;
+            MATCH_PER_STREAM_OPT(guess_layout_max, i, ist->guess_layout_max, ic, st);
+            guess_input_channel_layout(ist);
+            break;
+        case AVMEDIA_TYPE_DATA:
+        case AVMEDIA_TYPE_SUBTITLE: {
+            char *canvas_size = NULL;
+            MATCH_PER_STREAM_OPT(fix_sub_duration, i, ist->fix_sub_duration, ic, st);
+            MATCH_PER_STREAM_OPT(canvas_sizes, str, canvas_size, ic, st);
+            if (canvas_size &&
+                av_parse_video_size(&ist->dec_ctx->width, &ist->dec_ctx->height, canvas_size) < 0) {
+                av_log(NULL, AV_LOG_FATAL, "Invalid canvas size: %s.\n", canvas_size);
+                exit_program(1);
+            }
+            break;
+        }
+        case AVMEDIA_TYPE_ATTACHMENT:
+        case AVMEDIA_TYPE_UNKNOWN:
+            break;
+        default:
+            abort();
+        }
+
+        ist->par = avcodec_parameters_alloc();
+        if (!ist->par)
+            report_and_exit(AVERROR(ENOMEM));
+
+        ret = avcodec_parameters_from_context(ist->par, ist->dec_ctx);
+        if (ret < 0) {
+            av_log(NULL, AV_LOG_ERROR, "Error initializing the decoder context.\n");
+            exit_program(1);
+        }
+    }
+}
+
+static void dump_attachment(AVStream *st, const char *filename)
+{
+    int ret;
+    AVIOContext *out = NULL;
+    const AVDictionaryEntry *e;
+
+    if (!st->codecpar->extradata_size) {
+        av_log(NULL, AV_LOG_WARNING, "No extradata to dump in stream #%d:%d.\n",
+               nb_input_files - 1, st->index);
+        return;
+    }
+    if (!*filename && (e = av_dict_get(st->metadata, "filename", NULL, 0)))
+        filename = e->value;
+    if (!*filename) {
+        av_log(NULL, AV_LOG_FATAL, "No filename specified and no 'filename' tag"
+               "in stream #%d:%d.\n", nb_input_files - 1, st->index);
+        exit_program(1);
+    }
+
+    assert_file_overwrite(filename);
+
+    if ((ret = avio_open2(&out, filename, AVIO_FLAG_WRITE, &int_cb, NULL)) < 0) {
+        av_log(NULL, AV_LOG_FATAL, "Could not open file %s for writing.\n",
+               filename);
+        exit_program(1);
+    }
+
+    avio_write(out, st->codecpar->extradata, st->codecpar->extradata_size);
+    avio_flush(out);
+    avio_close(out);
+}
+
+int ifile_open(OptionsContext *o, const char *filename)
+{
+    InputFile *f;
+    AVFormatContext *ic;
+    const AVInputFormat *file_iformat = NULL;
+    int err, i, ret;
+    int64_t timestamp;
+    AVDictionary *unused_opts = NULL;
+    const AVDictionaryEntry *e = NULL;
+    char *   video_codec_name = NULL;
+    char *   audio_codec_name = NULL;
+    char *subtitle_codec_name = NULL;
+    char *    data_codec_name = NULL;
+    int scan_all_pmts_set = 0;
+
+    if (o->stop_time != INT64_MAX && o->recording_time != INT64_MAX) {
+        o->stop_time = INT64_MAX;
+        av_log(NULL, AV_LOG_WARNING, "-t and -to cannot be used together; using -t.\n");
+    }
+
+    if (o->stop_time != INT64_MAX && o->recording_time == INT64_MAX) {
+        int64_t start_time = o->start_time == AV_NOPTS_VALUE ? 0 : o->start_time;
+        if (o->stop_time <= start_time) {
+            av_log(NULL, AV_LOG_ERROR, "-to value smaller than -ss; aborting.\n");
+            exit_program(1);
+        } else {
+            o->recording_time = o->stop_time - start_time;
+        }
+    }
+
+    if (o->format) {
+        if (!(file_iformat = av_find_input_format(o->format))) {
+            av_log(NULL, AV_LOG_FATAL, "Unknown input format: '%s'\n", o->format);
+            exit_program(1);
+        }
+    }
+
+    if (!strcmp(filename, "-"))
+        filename = "pipe:";
+
+    stdin_interaction &= strncmp(filename, "pipe:", 5) &&
+                         strcmp(filename, "/dev/stdin");
+
+    /* get default parameters from command line */
+    ic = avformat_alloc_context();
+    if (!ic)
+        report_and_exit(AVERROR(ENOMEM));
+    if (o->nb_audio_sample_rate) {
+        av_dict_set_int(&o->g->format_opts, "sample_rate", o->audio_sample_rate[o->nb_audio_sample_rate - 1].u.i, 0);
+    }
+    if (o->nb_audio_channels) {
+        const AVClass *priv_class;
+        if (file_iformat && (priv_class = file_iformat->priv_class) &&
+            av_opt_find(&priv_class, "ch_layout", NULL, 0,
+                        AV_OPT_SEARCH_FAKE_OBJ)) {
+            char buf[32];
+            snprintf(buf, sizeof(buf), "%dC", o->audio_channels[o->nb_audio_channels - 1].u.i);
+            av_dict_set(&o->g->format_opts, "ch_layout", buf, 0);
+        }
+    }
+    if (o->nb_audio_ch_layouts) {
+        const AVClass *priv_class;
+        if (file_iformat && (priv_class = file_iformat->priv_class) &&
+            av_opt_find(&priv_class, "ch_layout", NULL, 0,
+                        AV_OPT_SEARCH_FAKE_OBJ)) {
+            av_dict_set(&o->g->format_opts, "ch_layout", o->audio_ch_layouts[o->nb_audio_ch_layouts - 1].u.str, 0);
+        }
+    }
+    if (o->nb_frame_rates) {
+        const AVClass *priv_class;
+        /* set the format-level framerate option;
+         * this is important for video grabbers, e.g. x11 */
+        if (file_iformat && (priv_class = file_iformat->priv_class) &&
+            av_opt_find(&priv_class, "framerate", NULL, 0,
+                        AV_OPT_SEARCH_FAKE_OBJ)) {
+            av_dict_set(&o->g->format_opts, "framerate",
+                        o->frame_rates[o->nb_frame_rates - 1].u.str, 0);
+        }
+    }
+    if (o->nb_frame_sizes) {
+        av_dict_set(&o->g->format_opts, "video_size", o->frame_sizes[o->nb_frame_sizes - 1].u.str, 0);
+    }
+    if (o->nb_frame_pix_fmts)
+        av_dict_set(&o->g->format_opts, "pixel_format", o->frame_pix_fmts[o->nb_frame_pix_fmts - 1].u.str, 0);
+
+    MATCH_PER_TYPE_OPT(codec_names, str,    video_codec_name, ic, "v");
+    MATCH_PER_TYPE_OPT(codec_names, str,    audio_codec_name, ic, "a");
+    MATCH_PER_TYPE_OPT(codec_names, str, subtitle_codec_name, ic, "s");
+    MATCH_PER_TYPE_OPT(codec_names, str,     data_codec_name, ic, "d");
+
+    if (video_codec_name)
+        ic->video_codec    = find_codec_or_die(video_codec_name   , AVMEDIA_TYPE_VIDEO   , 0);
+    if (audio_codec_name)
+        ic->audio_codec    = find_codec_or_die(audio_codec_name   , AVMEDIA_TYPE_AUDIO   , 0);
+    if (subtitle_codec_name)
+        ic->subtitle_codec = find_codec_or_die(subtitle_codec_name, AVMEDIA_TYPE_SUBTITLE, 0);
+    if (data_codec_name)
+        ic->data_codec     = find_codec_or_die(data_codec_name    , AVMEDIA_TYPE_DATA    , 0);
+
+    ic->video_codec_id     = video_codec_name    ? ic->video_codec->id    : AV_CODEC_ID_NONE;
+    ic->audio_codec_id     = audio_codec_name    ? ic->audio_codec->id    : AV_CODEC_ID_NONE;
+    ic->subtitle_codec_id  = subtitle_codec_name ? ic->subtitle_codec->id : AV_CODEC_ID_NONE;
+    ic->data_codec_id      = data_codec_name     ? ic->data_codec->id     : AV_CODEC_ID_NONE;
+
+    ic->flags |= AVFMT_FLAG_NONBLOCK;
+    if (o->bitexact)
+        ic->flags |= AVFMT_FLAG_BITEXACT;
+    ic->interrupt_callback = int_cb;
+
+    if (!av_dict_get(o->g->format_opts, "scan_all_pmts", NULL, AV_DICT_MATCH_CASE)) {
+        av_dict_set(&o->g->format_opts, "scan_all_pmts", "1", AV_DICT_DONT_OVERWRITE);
+        scan_all_pmts_set = 1;
+    }
+    /* open the input file with generic avformat function */
+    err = avformat_open_input(&ic, filename, file_iformat, &o->g->format_opts);
+    if (err < 0) {
+        print_error(filename, err);
+        if (err == AVERROR_PROTOCOL_NOT_FOUND)
+            av_log(NULL, AV_LOG_ERROR, "Did you mean file:%s?\n", filename);
+        exit_program(1);
+    }
+    if (scan_all_pmts_set)
+        av_dict_set(&o->g->format_opts, "scan_all_pmts", NULL, AV_DICT_MATCH_CASE);
+    remove_avoptions(&o->g->format_opts, o->g->codec_opts);
+    assert_avoptions(o->g->format_opts);
+
+    /* apply forced codec ids */
+    for (i = 0; i < ic->nb_streams; i++)
+        choose_decoder(o, ic, ic->streams[i], HWACCEL_NONE, AV_HWDEVICE_TYPE_NONE);
+
+    if (o->find_stream_info) {
+        AVDictionary **opts = setup_find_stream_info_opts(ic, o->g->codec_opts);
+        int orig_nb_streams = ic->nb_streams;
+
+        /* If not enough info to get the stream parameters, we decode the
+           first frames to get it. (used in mpeg case for example) */
+        ret = avformat_find_stream_info(ic, opts);
+
+        for (i = 0; i < orig_nb_streams; i++)
+            av_dict_free(&opts[i]);
+        av_freep(&opts);
+
+        if (ret < 0) {
+            av_log(NULL, AV_LOG_FATAL, "%s: could not find codec parameters\n", filename);
+            if (ic->nb_streams == 0) {
+                avformat_close_input(&ic);
+                exit_program(1);
+            }
+        }
+    }
+
+    if (o->start_time != AV_NOPTS_VALUE && o->start_time_eof != AV_NOPTS_VALUE) {
+        av_log(NULL, AV_LOG_WARNING, "Cannot use -ss and -sseof both, using -ss for %s\n", filename);
+        o->start_time_eof = AV_NOPTS_VALUE;
+    }
+
+    if (o->start_time_eof != AV_NOPTS_VALUE) {
+        if (o->start_time_eof >= 0) {
+            av_log(NULL, AV_LOG_ERROR, "-sseof value must be negative; aborting\n");
+            exit_program(1);
+        }
+        if (ic->duration > 0) {
+            o->start_time = o->start_time_eof + ic->duration;
+            if (o->start_time < 0) {
+                av_log(NULL, AV_LOG_WARNING, "-sseof value seeks to before start of file %s; ignored\n", filename);
+                o->start_time = AV_NOPTS_VALUE;
+            }
+        } else
+            av_log(NULL, AV_LOG_WARNING, "Cannot use -sseof, duration of %s not known\n", filename);
+    }
+    timestamp = (o->start_time == AV_NOPTS_VALUE) ? 0 : o->start_time;
+    /* add the stream start time */
+    if (!o->seek_timestamp && ic->start_time != AV_NOPTS_VALUE)
+        timestamp += ic->start_time;
+
+    /* if seeking requested, we execute it */
+    if (o->start_time != AV_NOPTS_VALUE) {
+        int64_t seek_timestamp = timestamp;
+
+        if (!(ic->iformat->flags & AVFMT_SEEK_TO_PTS)) {
+            int dts_heuristic = 0;
+            for (i=0; i<ic->nb_streams; i++) {
+                const AVCodecParameters *par = ic->streams[i]->codecpar;
+                if (par->video_delay) {
+                    dts_heuristic = 1;
+                    break;
+                }
+            }
+            if (dts_heuristic) {
+                seek_timestamp -= 3*AV_TIME_BASE / 23;
+            }
+        }
+        ret = avformat_seek_file(ic, -1, INT64_MIN, seek_timestamp, seek_timestamp, 0);
+        if (ret < 0) {
+            av_log(NULL, AV_LOG_WARNING, "%s: could not seek to position %0.3f\n",
+                   filename, (double)timestamp / AV_TIME_BASE);
+        }
+    }
+
+    /* update the current parameters so that they match the one of the input stream */
+    add_input_streams(o, ic);
+
+    /* dump the file content */
+    av_dump_format(ic, nb_input_files, filename, 0);
+
+    f = ALLOC_ARRAY_ELEM(input_files, nb_input_files);
+
+    f->ctx        = ic;
+    f->index      = nb_input_files - 1;
+    f->ist_index  = nb_input_streams - ic->nb_streams;
+    f->start_time = o->start_time;
+    f->recording_time = o->recording_time;
+    f->input_sync_ref = o->input_sync_ref;
+    f->input_ts_offset = o->input_ts_offset;
+    f->ts_offset  = o->input_ts_offset - (copy_ts ? (start_at_zero && ic->start_time != AV_NOPTS_VALUE ? ic->start_time : 0) : timestamp);
+    f->nb_streams = ic->nb_streams;
+    f->rate_emu   = o->rate_emu;
+    f->accurate_seek = o->accurate_seek;
+    f->loop = o->loop;
+    f->duration = 0;
+    f->time_base = (AVRational){ 1, 1 };
+
+    f->readrate = o->readrate ? o->readrate : 0.0;
+    if (f->readrate < 0.0f) {
+        av_log(NULL, AV_LOG_ERROR, "Option -readrate for Input #%d is %0.3f; it must be non-negative.\n", f->index, f->readrate);
+        exit_program(1);
+    }
+    if (f->readrate && f->rate_emu) {
+        av_log(NULL, AV_LOG_WARNING, "Both -readrate and -re set for Input #%d. Using -readrate %0.3f.\n", f->index, f->readrate);
+        f->rate_emu = 0;
+    }
+
+    f->thread_queue_size = o->thread_queue_size;
+
+    /* check if all codec options have been used */
+    unused_opts = strip_specifiers(o->g->codec_opts);
+    for (i = f->ist_index; i < nb_input_streams; i++) {
+        e = NULL;
+        while ((e = av_dict_get(input_streams[i]->decoder_opts, "", e,
+                                AV_DICT_IGNORE_SUFFIX)))
+            av_dict_set(&unused_opts, e->key, NULL, 0);
+    }
+
+    e = NULL;
+    while ((e = av_dict_get(unused_opts, "", e, AV_DICT_IGNORE_SUFFIX))) {
+        const AVClass *class = avcodec_get_class();
+        const AVOption *option = av_opt_find(&class, e->key, NULL, 0,
+                                             AV_OPT_SEARCH_CHILDREN | AV_OPT_SEARCH_FAKE_OBJ);
+        const AVClass *fclass = avformat_get_class();
+        const AVOption *foption = av_opt_find(&fclass, e->key, NULL, 0,
+                                             AV_OPT_SEARCH_CHILDREN | AV_OPT_SEARCH_FAKE_OBJ);
+        if (!option || foption)
+            continue;
+
+
+        if (!(option->flags & AV_OPT_FLAG_DECODING_PARAM)) {
+            av_log(NULL, AV_LOG_ERROR, "Codec AVOption %s (%s) specified for "
+                   "input file #%d (%s) is not a decoding option.\n", e->key,
+                   option->help ? option->help : "", f->index,
+                   filename);
+            exit_program(1);
+        }
+
+        av_log(NULL, AV_LOG_WARNING, "Codec AVOption %s (%s) specified for "
+               "input file #%d (%s) has not been used for any stream. The most "
+               "likely reason is either wrong type (e.g. a video option with "
+               "no video streams) or that it is a private option of some decoder "
+               "which was not actually used for any stream.\n", e->key,
+               option->help ? option->help : "", f->index, filename);
+    }
+    av_dict_free(&unused_opts);
+
+    for (i = 0; i < o->nb_dump_attachment; i++) {
+        int j;
+
+        for (j = 0; j < ic->nb_streams; j++) {
+            AVStream *st = ic->streams[j];
+
+            if (check_stream_specifier(ic, st, o->dump_attachment[i].specifier) == 1)
+                dump_attachment(st, o->dump_attachment[i].u.str);
+        }
+    }
+
+    input_stream_potentially_available = 1;
+
+    return 0;
+}