diff --git a/fftools/Makefile b/fftools/Makefile
index 9939c7095c..56820e6bc8 100644
--- a/fftools/Makefile
+++ b/fftools/Makefile
@@ -10,6 +10,7 @@ ALLAVPROGS   = $(AVBASENAMES:%=%$(PROGSSUF)$(EXESUF))
 ALLAVPROGS_G = $(AVBASENAMES:%=%$(PROGSSUF)_g$(EXESUF))
 
 OBJS-ffmpeg +=                  \
+    fftools/ffmpeg_dec.o        \
     fftools/ffmpeg_demux.o      \
     fftools/ffmpeg_enc.o        \
     fftools/ffmpeg_filter.o     \
diff --git a/fftools/ffmpeg.c b/fftools/ffmpeg.c
index 57bdc12473..d8b06eb724 100644
--- a/fftools/ffmpeg.c
+++ b/fftools/ffmpeg.c
@@ -621,11 +621,6 @@ void assert_avoptions(AVDictionary *m)
     }
 }
 
-static void abort_codec_experimental(const AVCodec *c, int encoder)
-{
-    exit_program(1);
-}
-
 void update_benchmark(const char *fmt, ...)
 {
     if (do_benchmark_all) {
@@ -1858,110 +1853,6 @@ static int process_input_packet(InputStream *ist, const AVPacket *pkt, int no_eo
     return !eof_reached;
 }
 
-static enum AVPixelFormat get_format(AVCodecContext *s, const enum AVPixelFormat *pix_fmts)
-{
-    InputStream *ist = s->opaque;
-    const enum AVPixelFormat *p;
-    int ret;
-
-    for (p = pix_fmts; *p != AV_PIX_FMT_NONE; p++) {
-        const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(*p);
-        const AVCodecHWConfig  *config = NULL;
-        int i;
-
-        if (!(desc->flags & AV_PIX_FMT_FLAG_HWACCEL))
-            break;
-
-        if (ist->hwaccel_id == HWACCEL_GENERIC ||
-            ist->hwaccel_id == HWACCEL_AUTO) {
-            for (i = 0;; i++) {
-                config = avcodec_get_hw_config(s->codec, i);
-                if (!config)
-                    break;
-                if (!(config->methods &
-                      AV_CODEC_HW_CONFIG_METHOD_HW_DEVICE_CTX))
-                    continue;
-                if (config->pix_fmt == *p)
-                    break;
-            }
-        }
-        if (config && config->device_type == ist->hwaccel_device_type) {
-            ret = hwaccel_decode_init(s);
-            if (ret < 0) {
-                if (ist->hwaccel_id == HWACCEL_GENERIC) {
-                    av_log(NULL, AV_LOG_FATAL,
-                           "%s hwaccel requested for input stream #%d:%d, "
-                           "but cannot be initialized.\n",
-                           av_hwdevice_get_type_name(config->device_type),
-                           ist->file_index, ist->st->index);
-                    return AV_PIX_FMT_NONE;
-                }
-                continue;
-            }
-
-            ist->hwaccel_pix_fmt = *p;
-            break;
-        }
-    }
-
-    return *p;
-}
-
-static int init_input_stream(InputStream *ist)
-{
-    int ret;
-
-    if (ist->decoding_needed) {
-        const AVCodec *codec = ist->dec;
-        if (!codec) {
-            av_log(ist, AV_LOG_ERROR,
-                   "Decoding requested, but no decoder found for: %s\n",
-                    avcodec_get_name(ist->dec_ctx->codec_id));
-            return AVERROR(EINVAL);
-        }
-
-        ist->dec_ctx->opaque                = ist;
-        ist->dec_ctx->get_format            = get_format;
-
-        if (ist->dec_ctx->codec_id == AV_CODEC_ID_DVB_SUBTITLE &&
-           (ist->decoding_needed & DECODING_FOR_OST)) {
-            av_dict_set(&ist->decoder_opts, "compute_edt", "1", AV_DICT_DONT_OVERWRITE);
-            if (ist->decoding_needed & DECODING_FOR_FILTER)
-                av_log(NULL, AV_LOG_WARNING, "Warning using DVB subtitles for filtering and output at the same time is not fully supported, also see -compute_edt [0|1]\n");
-        }
-
-        /* Useful for subtitles retiming by lavf (FIXME), skipping samples in
-         * audio, and video decoders such as cuvid or mediacodec */
-        ist->dec_ctx->pkt_timebase = ist->st->time_base;
-
-        if (!av_dict_get(ist->decoder_opts, "threads", NULL, 0))
-            av_dict_set(&ist->decoder_opts, "threads", "auto", 0);
-        /* Attached pics are sparse, therefore we would not want to delay their decoding till EOF. */
-        if (ist->st->disposition & AV_DISPOSITION_ATTACHED_PIC)
-            av_dict_set(&ist->decoder_opts, "threads", "1", 0);
-
-        ret = hw_device_setup_for_decode(ist);
-        if (ret < 0) {
-            av_log(ist, AV_LOG_ERROR,
-                   "Hardware device setup failed for decoder: %s\n",
-                   av_err2str(ret));
-            return ret;
-        }
-
-        if ((ret = avcodec_open2(ist->dec_ctx, codec, &ist->decoder_opts)) < 0) {
-            if (ret == AVERROR_EXPERIMENTAL)
-                abort_codec_experimental(codec, 0);
-
-            av_log(ist, AV_LOG_ERROR, "Error while opening decoder: %s\n",
-                   av_err2str(ret));
-            return ret;
-        }
-        assert_avoptions(ist->decoder_opts);
-    }
-
-    return 0;
-}
-
 static int init_output_stream_nofilter(OutputStream *ost)
 {
     int ret = 0;
@@ -1993,7 +1884,7 @@ static int transcode_init(void)
 
     /* init input streams */
     for (InputStream *ist = ist_iter(NULL); ist; ist = ist_iter(ist))
-        if ((ret = init_input_stream(ist)) < 0)
+        if (ist->decoding_needed && (ret = dec_open(ist)) < 0)
             goto dump_format;
 
     /*
diff --git a/fftools/ffmpeg.h b/fftools/ffmpeg.h
index c73fc8a459..5833c13812 100644
--- a/fftools/ffmpeg.h
+++ b/fftools/ffmpeg.h
@@ -829,6 +829,8 @@ AVBufferRef *hw_device_for_filter(void);
 
 int hwaccel_decode_init(AVCodecContext *avctx);
 
+int dec_open(InputStream *ist);
+
 int enc_alloc(Encoder **penc, const AVCodec *codec);
 void enc_free(Encoder **penc);
 
diff --git a/fftools/ffmpeg_dec.c b/fftools/ffmpeg_dec.c
new file mode 100644
index 0000000000..ccf558649c
--- /dev/null
+++ b/fftools/ffmpeg_dec.c
@@ -0,0 +1,135 @@
+/*
+ * 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 "libavutil/dict.h"
+#include "libavutil/error.h"
+#include "libavutil/log.h"
+#include "libavutil/pixdesc.h"
+#include "libavutil/pixfmt.h"
+
+#include "libavcodec/avcodec.h"
+#include "libavcodec/codec.h"
+
+#include "ffmpeg.h"
+
+static void abort_codec_experimental(const AVCodec *c, int encoder)
+{
+    exit_program(1);
+}
+
+static enum AVPixelFormat get_format(AVCodecContext *s, const enum AVPixelFormat *pix_fmts)
+{
+    InputStream *ist = s->opaque;
+    const enum AVPixelFormat *p;
+    int ret;
+
+    for (p = pix_fmts; *p != AV_PIX_FMT_NONE; p++) {
+        const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(*p);
+        const AVCodecHWConfig  *config = NULL;
+        int i;
+
+        if (!(desc->flags & AV_PIX_FMT_FLAG_HWACCEL))
+            break;
+
+        if (ist->hwaccel_id == HWACCEL_GENERIC ||
+            ist->hwaccel_id == HWACCEL_AUTO) {
+            for (i = 0;; i++) {
+                config = avcodec_get_hw_config(s->codec, i);
+                if (!config)
+                    break;
+                if (!(config->methods &
+                      AV_CODEC_HW_CONFIG_METHOD_HW_DEVICE_CTX))
+                    continue;
+                if (config->pix_fmt == *p)
+                    break;
+            }
+        }
+        if (config && config->device_type == ist->hwaccel_device_type) {
+            ret = hwaccel_decode_init(s);
+            if (ret < 0) {
+                if (ist->hwaccel_id == HWACCEL_GENERIC) {
+                    av_log(NULL, AV_LOG_FATAL,
+                           "%s hwaccel requested for input stream #%d:%d, "
+                           "but cannot be initialized.\n",
+                           av_hwdevice_get_type_name(config->device_type),
+                           ist->file_index, ist->st->index);
+                    return AV_PIX_FMT_NONE;
+                }
+                continue;
+            }
+
+            ist->hwaccel_pix_fmt = *p;
+            break;
+        }
+    }
+
+    return *p;
+}
+
+int dec_open(InputStream *ist)
+{
+        const AVCodec *codec = ist->dec;
+    int ret;
+
+        if (!codec) {
+            av_log(ist, AV_LOG_ERROR,
+                   "Decoding requested, but no decoder found for: %s\n",
+                    avcodec_get_name(ist->dec_ctx->codec_id));
+            return AVERROR(EINVAL);
+        }
+
+        ist->dec_ctx->opaque                = ist;
+        ist->dec_ctx->get_format            = get_format;
+
+        if (ist->dec_ctx->codec_id == AV_CODEC_ID_DVB_SUBTITLE &&
+           (ist->decoding_needed & DECODING_FOR_OST)) {
+            av_dict_set(&ist->decoder_opts, "compute_edt", "1", AV_DICT_DONT_OVERWRITE);
+            if (ist->decoding_needed & DECODING_FOR_FILTER)
+                av_log(NULL, AV_LOG_WARNING, "Warning using DVB subtitles for filtering and output at the same time is not fully supported, also see -compute_edt [0|1]\n");
+        }
+
+        /* Useful for subtitles retiming by lavf (FIXME), skipping samples in
+         * audio, and video decoders such as cuvid or mediacodec */
+        ist->dec_ctx->pkt_timebase = ist->st->time_base;
+
+        if (!av_dict_get(ist->decoder_opts, "threads", NULL, 0))
+            av_dict_set(&ist->decoder_opts, "threads", "auto", 0);
+        /* Attached pics are sparse, therefore we would not want to delay their decoding till EOF. */
+        if (ist->st->disposition & AV_DISPOSITION_ATTACHED_PIC)
+            av_dict_set(&ist->decoder_opts, "threads", "1", 0);
+
+        ret = hw_device_setup_for_decode(ist);
+        if (ret < 0) {
+            av_log(ist, AV_LOG_ERROR,
+                   "Hardware device setup failed for decoder: %s\n",
+                   av_err2str(ret));
+            return ret;
+        }
+
+        if ((ret = avcodec_open2(ist->dec_ctx, codec, &ist->decoder_opts)) < 0) {
+            if (ret == AVERROR_EXPERIMENTAL)
+                abort_codec_experimental(codec, 0);
+
+            av_log(ist, AV_LOG_ERROR, "Error while opening decoder: %s\n",
+                   av_err2str(ret));
+            return ret;
+        }
+        assert_avoptions(ist->decoder_opts);
+
+    return 0;
+}
