adding ffmpeg specific version

1 files changed, 813 insertions, 0 deletions

diff --git a/ffmpeg1/libavcodec/h264_refs.c b/ffmpeg1/libavcodec/h264_refs.c
new file mode 100644
index 0000000..c3e7b7c
--- /dev/null
+++ b/ffmpeg1/libavcodec/h264_refs.c
@@ -0,0 +1,813 @@
+/*
+ * H.26L/H.264/AVC/JVT/14496-10/... reference picture handling
+ * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
+ *
+ * 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
+ * H.264 / AVC / MPEG4 part10  reference picture handling.
+ * @author Michael Niedermayer <michaelni@gmx.at>
+ */
+
+#include "libavutil/avassert.h"
+#include "internal.h"
+#include "avcodec.h"
+#include "h264.h"
+#include "golomb.h"
+
+//#undef NDEBUG
+#include <assert.h>
+
+#define COPY_PICTURE(dst, src) \
+do {\
+    *(dst) = *(src);\
+    (dst)->f.extended_data = (dst)->f.data;\
+    (dst)->tf.f = &(dst)->f;\
+} while (0)
+
+
+static void pic_as_field(Picture *pic, const int parity){
+    int i;
+    for (i = 0; i < 4; ++i) {
+        if (parity == PICT_BOTTOM_FIELD)
+            pic->f.data[i] += pic->f.linesize[i];
+        pic->reference      = parity;
+        pic->f.linesize[i] *= 2;
+    }
+    pic->poc= pic->field_poc[parity == PICT_BOTTOM_FIELD];
+}
+
+static int split_field_copy(Picture *dest, Picture *src, int parity, int id_add)
+{
+    int match = !!(src->reference & parity);
+
+    if (match) {
+        COPY_PICTURE(dest, src);
+        if (parity != PICT_FRAME) {
+            pic_as_field(dest, parity);
+            dest->pic_id *= 2;
+            dest->pic_id += id_add;
+        }
+    }
+
+    return match;
+}
+
+static int build_def_list(Picture *def, Picture **in, int len, int is_long, int sel)
+{
+    int  i[2] = { 0 };
+    int index = 0;
+
+    while (i[0] < len || i[1] < len) {
+        while (i[0] < len && !(in[i[0]] && (in[i[0]]->reference & sel)))
+            i[0]++;
+        while (i[1] < len && !(in[i[1]] && (in[i[1]]->reference & (sel ^ 3))))
+            i[1]++;
+        if (i[0] < len) {
+            in[i[0]]->pic_id = is_long ? i[0] : in[i[0]]->frame_num;
+            split_field_copy(&def[index++], in[i[0]++], sel, 1);
+        }
+        if (i[1] < len) {
+            in[i[1]]->pic_id = is_long ? i[1] : in[i[1]]->frame_num;
+            split_field_copy(&def[index++], in[i[1]++], sel ^ 3, 0);
+        }
+    }
+
+    return index;
+}
+
+static int add_sorted(Picture **sorted, Picture **src, int len, int limit, int dir)
+{
+    int i, best_poc;
+    int out_i = 0;
+
+    for (;;) {
+        best_poc = dir ? INT_MIN : INT_MAX;
+
+        for (i = 0; i < len; i++) {
+            const int poc = src[i]->poc;
+            if (((poc > limit) ^ dir) && ((poc < best_poc) ^ dir)) {
+                best_poc      = poc;
+                sorted[out_i] = src[i];
+            }
+        }
+        if (best_poc == (dir ? INT_MIN : INT_MAX))
+            break;
+        limit = sorted[out_i++]->poc - dir;
+    }
+    return out_i;
+}
+
+int ff_h264_fill_default_ref_list(H264Context *h)
+{
+    int i, len;
+
+    if (h->slice_type_nos == AV_PICTURE_TYPE_B) {
+        Picture *sorted[32];
+        int cur_poc, list;
+        int lens[2];
+
+        if (FIELD_PICTURE(h))
+            cur_poc = h->cur_pic_ptr->field_poc[h->picture_structure == PICT_BOTTOM_FIELD];
+        else
+            cur_poc = h->cur_pic_ptr->poc;
+
+        for (list = 0; list < 2; list++) {
+            len  = add_sorted(sorted,       h->short_ref, h->short_ref_count, cur_poc, 1 ^ list);
+            len += add_sorted(sorted + len, h->short_ref, h->short_ref_count, cur_poc, 0 ^ list);
+            av_assert0(len <= 32);
+            len  = build_def_list(h->default_ref_list[list],       sorted,      len, 0, h->picture_structure);
+            len += build_def_list(h->default_ref_list[list] + len, h->long_ref, 16,  1, h->picture_structure);
+            av_assert0(len <= 32);
+
+            if (len < h->ref_count[list])
+                memset(&h->default_ref_list[list][len], 0, sizeof(Picture) * (h->ref_count[list] - len));
+            lens[list] = len;
+        }
+
+        if (lens[0] == lens[1] && lens[1] > 1) {
+            for (i = 0; h->default_ref_list[0][i].f.data[0] == h->default_ref_list[1][i].f.data[0] && i < lens[0]; i++);
+            if (i == lens[0]) {
+                Picture tmp;
+                COPY_PICTURE(&tmp, &h->default_ref_list[1][0]);
+                COPY_PICTURE(&h->default_ref_list[1][0], &h->default_ref_list[1][1]);
+                COPY_PICTURE(&h->default_ref_list[1][1], &tmp);
+            }
+        }
+    } else {
+        len  = build_def_list(h->default_ref_list[0],       h->short_ref, h->short_ref_count, 0, h->picture_structure);
+        len += build_def_list(h->default_ref_list[0] + len, h-> long_ref, 16,                 1, h->picture_structure);
+        av_assert0(len <= 32);
+        if (len < h->ref_count[0])
+            memset(&h->default_ref_list[0][len], 0, sizeof(Picture) * (h->ref_count[0] - len));
+    }
+#ifdef TRACE
+    for (i = 0; i < h->ref_count[0]; i++) {
+        tprintf(h->avctx, "List0: %s fn:%d 0x%p\n",
+                (h->default_ref_list[0][i].long_ref ? "LT" : "ST"),
+                h->default_ref_list[0][i].pic_id,
+                h->default_ref_list[0][i].f.data[0]);
+    }
+    if (h->slice_type_nos == AV_PICTURE_TYPE_B) {
+        for (i = 0; i < h->ref_count[1]; i++) {
+            tprintf(h->avctx, "List1: %s fn:%d 0x%p\n",
+                    (h->default_ref_list[1][i].long_ref ? "LT" : "ST"),
+                    h->default_ref_list[1][i].pic_id,
+                    h->default_ref_list[1][i].f.data[0]);
+        }
+    }
+#endif
+    return 0;
+}
+
+static void print_short_term(H264Context *h);
+static void print_long_term(H264Context *h);
+
+/**
+ * Extract structure information about the picture described by pic_num in
+ * the current decoding context (frame or field). Note that pic_num is
+ * picture number without wrapping (so, 0<=pic_num<max_pic_num).
+ * @param pic_num picture number for which to extract structure information
+ * @param structure one of PICT_XXX describing structure of picture
+ *                      with pic_num
+ * @return frame number (short term) or long term index of picture
+ *         described by pic_num
+ */
+static int pic_num_extract(H264Context *h, int pic_num, int *structure)
+{
+    *structure = h->picture_structure;
+    if (FIELD_PICTURE(h)) {
+        if (!(pic_num & 1))
+            /* opposite field */
+            *structure ^= PICT_FRAME;
+        pic_num >>= 1;
+    }
+
+    return pic_num;
+}
+
+int ff_h264_decode_ref_pic_list_reordering(H264Context *h)
+{
+    int list, index, pic_structure, i;
+
+    print_short_term(h);
+    print_long_term(h);
+
+    for (list = 0; list < h->list_count; list++) {
+        for (i = 0; i < h->ref_count[list]; i++)
+            COPY_PICTURE(&h->ref_list[list][i], &h->default_ref_list[list][i]);
+
+        if (get_bits1(&h->gb)) {
+            int pred = h->curr_pic_num;
+
+            for (index = 0; ; index++) {
+                unsigned int reordering_of_pic_nums_idc = get_ue_golomb_31(&h->gb);
+                unsigned int pic_id;
+                int i;
+                Picture *ref = NULL;
+
+                if (reordering_of_pic_nums_idc == 3)
+                    break;
+
+                if (index >= h->ref_count[list]) {
+                    av_log(h->avctx, AV_LOG_ERROR, "reference count overflow\n");
+                    return -1;
+                }
+
+                if (reordering_of_pic_nums_idc < 3) {
+                    if (reordering_of_pic_nums_idc < 2) {
+                        const unsigned int abs_diff_pic_num = get_ue_golomb(&h->gb) + 1;
+                        int frame_num;
+
+                        if (abs_diff_pic_num > h->max_pic_num) {
+                            av_log(h->avctx, AV_LOG_ERROR, "abs_diff_pic_num overflow\n");
+                            return -1;
+                        }
+
+                        if (reordering_of_pic_nums_idc == 0)
+                            pred -= abs_diff_pic_num;
+                        else
+                            pred += abs_diff_pic_num;
+                        pred &= h->max_pic_num - 1;
+
+                        frame_num = pic_num_extract(h, pred, &pic_structure);
+
+                        for (i = h->short_ref_count - 1; i >= 0; i--) {
+                            ref = h->short_ref[i];
+                            assert(ref->reference);
+                            assert(!ref->long_ref);
+                            if (ref->frame_num == frame_num &&
+                                (ref->reference & pic_structure))
+                                break;
+                        }
+                        if (i >= 0)
+                            ref->pic_id = pred;
+                    } else {
+                        int long_idx;
+                        pic_id = get_ue_golomb(&h->gb); //long_term_pic_idx
+
+                        long_idx = pic_num_extract(h, pic_id, &pic_structure);
+
+                        if (long_idx > 31) {
+                            av_log(h->avctx, AV_LOG_ERROR, "long_term_pic_idx overflow\n");
+                            return -1;
+                        }
+                        ref = h->long_ref[long_idx];
+                        assert(!(ref && !ref->reference));
+                        if (ref && (ref->reference & pic_structure)) {
+                            ref->pic_id = pic_id;
+                            assert(ref->long_ref);
+                            i = 0;
+                        } else {
+                            i = -1;
+                        }
+                    }
+
+                    if (i < 0) {
+                        av_log(h->avctx, AV_LOG_ERROR, "reference picture missing during reorder\n");
+                        memset(&h->ref_list[list][index], 0, sizeof(Picture)); //FIXME
+                    } else {
+                        for (i = index; i + 1 < h->ref_count[list]; i++) {
+                            if (ref->long_ref == h->ref_list[list][i].long_ref &&
+                                ref->pic_id   == h->ref_list[list][i].pic_id)
+                                break;
+                        }
+                        for (; i > index; i--) {
+                            COPY_PICTURE(&h->ref_list[list][i], &h->ref_list[list][i - 1]);
+                        }
+                        COPY_PICTURE(&h->ref_list[list][index], ref);
+                        if (FIELD_PICTURE(h)) {
+                            pic_as_field(&h->ref_list[list][index], pic_structure);
+                        }
+                    }
+                } else {
+                    av_log(h->avctx, AV_LOG_ERROR, "illegal reordering_of_pic_nums_idc\n");
+                    return -1;
+                }
+            }
+        }
+    }
+    for (list = 0; list < h->list_count; list++) {
+        for (index = 0; index < h->ref_count[list]; index++) {
+            if (   !h->ref_list[list][index].f.data[0]
+                || (!FIELD_PICTURE(h) && (h->ref_list[list][index].reference&3) != 3)) {
+                int i;
+                av_log(h->avctx, AV_LOG_ERROR, "Missing reference picture, default is %d\n", h->default_ref_list[list][0].poc);
+                for (i = 0; i < FF_ARRAY_ELEMS(h->last_pocs); i++)
+                    h->last_pocs[i] = INT_MIN;
+                if (h->default_ref_list[list][0].f.data[0]
+                    && !(!FIELD_PICTURE(h) && (h->default_ref_list[list][0].reference&3) != 3))
+                    COPY_PICTURE(&h->ref_list[list][index], &h->default_ref_list[list][0]);
+                else
+                    return -1;
+            }
+        }
+    }
+
+    return 0;
+}
+
+void ff_h264_fill_mbaff_ref_list(H264Context *h)
+{
+    int list, i, j;
+    for (list = 0; list < h->list_count; list++) {
+        for (i = 0; i < h->ref_count[list]; i++) {
+            Picture *frame = &h->ref_list[list][i];
+            Picture *field = &h->ref_list[list][16 + 2 * i];
+            COPY_PICTURE(field, frame);
+            for (j = 0; j < 3; j++)
+                field[0].f.linesize[j] <<= 1;
+            field[0].reference = PICT_TOP_FIELD;
+            field[0].poc       = field[0].field_poc[0];
+            COPY_PICTURE(field + 1, field);
+            for (j = 0; j < 3; j++)
+                field[1].f.data[j] += frame->f.linesize[j];
+            field[1].reference = PICT_BOTTOM_FIELD;
+            field[1].poc       = field[1].field_poc[1];
+
+            h->luma_weight[16 + 2 * i][list][0] = h->luma_weight[16 + 2 * i + 1][list][0] = h->luma_weight[i][list][0];
+            h->luma_weight[16 + 2 * i][list][1] = h->luma_weight[16 + 2 * i + 1][list][1] = h->luma_weight[i][list][1];
+            for (j = 0; j < 2; j++) {
+                h->chroma_weight[16 + 2 * i][list][j][0] = h->chroma_weight[16 + 2 * i + 1][list][j][0] = h->chroma_weight[i][list][j][0];
+                h->chroma_weight[16 + 2 * i][list][j][1] = h->chroma_weight[16 + 2 * i + 1][list][j][1] = h->chroma_weight[i][list][j][1];
+            }
+        }
+    }
+}
+
+/**
+ * Mark a picture as no longer needed for reference. The refmask
+ * argument allows unreferencing of individual fields or the whole frame.
+ * If the picture becomes entirely unreferenced, but is being held for
+ * display purposes, it is marked as such.
+ * @param refmask mask of fields to unreference; the mask is bitwise
+ *                anded with the reference marking of pic
+ * @return non-zero if pic becomes entirely unreferenced (except possibly
+ *         for display purposes) zero if one of the fields remains in
+ *         reference
+ */
+static inline int unreference_pic(H264Context *h, Picture *pic, int refmask)
+{
+    int i;
+    if (pic->reference &= refmask) {
+        return 0;
+    } else {
+        for(i = 0; h->delayed_pic[i]; i++)
+            if(pic == h->delayed_pic[i]){
+                pic->reference = DELAYED_PIC_REF;
+                break;
+            }
+        return 1;
+    }
+}
+
+/**
+ * Find a Picture in the short term reference list by frame number.
+ * @param frame_num frame number to search for
+ * @param idx the index into h->short_ref where returned picture is found
+ *            undefined if no picture found.
+ * @return pointer to the found picture, or NULL if no pic with the provided
+ *                 frame number is found
+ */
+static Picture *find_short(H264Context *h, int frame_num, int *idx)
+{
+    int i;
+
+    for (i = 0; i < h->short_ref_count; i++) {
+        Picture *pic = h->short_ref[i];
+        if (h->avctx->debug & FF_DEBUG_MMCO)
+            av_log(h->avctx, AV_LOG_DEBUG, "%d %d %p\n", i, pic->frame_num, pic);
+        if (pic->frame_num == frame_num) {
+            *idx = i;
+            return pic;
+        }
+    }
+    return NULL;
+}
+
+/**
+ * Remove a picture from the short term reference list by its index in
+ * that list.  This does no checking on the provided index; it is assumed
+ * to be valid. Other list entries are shifted down.
+ * @param i index into h->short_ref of picture to remove.
+ */
+static void remove_short_at_index(H264Context *h, int i)
+{
+    assert(i >= 0 && i < h->short_ref_count);
+    h->short_ref[i] = NULL;
+    if (--h->short_ref_count)
+        memmove(&h->short_ref[i], &h->short_ref[i + 1],
+                (h->short_ref_count - i) * sizeof(Picture*));
+}
+
+/**
+ *
+ * @return the removed picture or NULL if an error occurs
+ */
+static Picture *remove_short(H264Context *h, int frame_num, int ref_mask)
+{
+    Picture *pic;
+    int i;
+
+    if (h->avctx->debug & FF_DEBUG_MMCO)
+        av_log(h->avctx, AV_LOG_DEBUG, "remove short %d count %d\n", frame_num, h->short_ref_count);
+
+    pic = find_short(h, frame_num, &i);
+    if (pic) {
+        if (unreference_pic(h, pic, ref_mask))
+            remove_short_at_index(h, i);
+    }
+
+    return pic;
+}
+
+/**
+ * Remove a picture from the long term reference list by its index in
+ * that list.
+ * @return the removed picture or NULL if an error occurs
+ */
+static Picture *remove_long(H264Context *h, int i, int ref_mask)
+{
+    Picture *pic;
+
+    pic = h->long_ref[i];
+    if (pic) {
+        if (unreference_pic(h, pic, ref_mask)) {
+            assert(h->long_ref[i]->long_ref == 1);
+            h->long_ref[i]->long_ref = 0;
+            h->long_ref[i]           = NULL;
+            h->long_ref_count--;
+        }
+    }
+
+    return pic;
+}
+
+void ff_h264_remove_all_refs(H264Context *h)
+{
+    int i;
+
+    for (i = 0; i < 16; i++) {
+        remove_long(h, i, 0);
+    }
+    assert(h->long_ref_count == 0);
+
+    for (i = 0; i < h->short_ref_count; i++) {
+        unreference_pic(h, h->short_ref[i], 0);
+        h->short_ref[i] = NULL;
+    }
+    h->short_ref_count = 0;
+
+    memset(h->default_ref_list, 0, sizeof(h->default_ref_list));
+    memset(h->ref_list, 0, sizeof(h->ref_list));
+}
+
+/**
+ * print short term list
+ */
+static void print_short_term(H264Context *h)
+{
+    uint32_t i;
+    if (h->avctx->debug & FF_DEBUG_MMCO) {
+        av_log(h->avctx, AV_LOG_DEBUG, "short term list:\n");
+        for (i = 0; i < h->short_ref_count; i++) {
+            Picture *pic = h->short_ref[i];
+            av_log(h->avctx, AV_LOG_DEBUG, "%d fn:%d poc:%d %p\n",
+                   i, pic->frame_num, pic->poc, pic->f.data[0]);
+        }
+    }
+}
+
+/**
+ * print long term list
+ */
+static void print_long_term(H264Context *h)
+{
+    uint32_t i;
+    if (h->avctx->debug & FF_DEBUG_MMCO) {
+        av_log(h->avctx, AV_LOG_DEBUG, "long term list:\n");
+        for (i = 0; i < 16; i++) {
+            Picture *pic = h->long_ref[i];
+            if (pic) {
+                av_log(h->avctx, AV_LOG_DEBUG, "%d fn:%d poc:%d %p\n",
+                       i, pic->frame_num, pic->poc, pic->f.data[0]);
+            }
+        }
+    }
+}
+
+static int check_opcodes(MMCO *mmco1, MMCO *mmco2, int n_mmcos)
+{
+    int i;
+
+    for (i = 0; i < n_mmcos; i++) {
+        if (mmco1[i].opcode != mmco2[i].opcode) {
+            av_log(NULL, AV_LOG_ERROR, "MMCO opcode [%d, %d] at %d mismatches between slices\n",
+                   mmco1[i].opcode, mmco2[i].opcode, i);
+            return -1;
+        }
+    }
+
+    return 0;
+}
+
+int ff_generate_sliding_window_mmcos(H264Context *h, int first_slice)
+{
+    MMCO mmco_temp[MAX_MMCO_COUNT], *mmco = first_slice ? h->mmco : mmco_temp;
+    int mmco_index = 0, i;
+
+    if (h->short_ref_count &&
+        h->long_ref_count + h->short_ref_count >= h->sps.ref_frame_count &&
+        !(FIELD_PICTURE(h) && !h->first_field && h->cur_pic_ptr->reference)) {
+        mmco[0].opcode        = MMCO_SHORT2UNUSED;
+        mmco[0].short_pic_num = h->short_ref[h->short_ref_count - 1]->frame_num;
+        mmco_index            = 1;
+        if (FIELD_PICTURE(h)) {
+            mmco[0].short_pic_num *= 2;
+            mmco[1].opcode         = MMCO_SHORT2UNUSED;
+            mmco[1].short_pic_num  = mmco[0].short_pic_num + 1;
+            mmco_index             = 2;
+        }
+    }
+
+    if (first_slice) {
+        h->mmco_index = mmco_index;
+    } else if (!first_slice && mmco_index >= 0 &&
+               (mmco_index != h->mmco_index ||
+                (i = check_opcodes(h->mmco, mmco_temp, mmco_index)))) {
+        av_log(h->avctx, AV_LOG_ERROR,
+               "Inconsistent MMCO state between slices [%d, %d]\n",
+               mmco_index, h->mmco_index);
+        return AVERROR_INVALIDDATA;
+    }
+    return 0;
+}
+
+int ff_h264_execute_ref_pic_marking(H264Context *h, MMCO *mmco, int mmco_count)
+{
+    int i, av_uninit(j);
+    int current_ref_assigned = 0, err = 0;
+    Picture *av_uninit(pic);
+
+    if ((h->avctx->debug & FF_DEBUG_MMCO) && mmco_count == 0)
+        av_log(h->avctx, AV_LOG_DEBUG, "no mmco here\n");
+
+    for (i = 0; i < mmco_count; i++) {
+        int av_uninit(structure), av_uninit(frame_num);
+        if (h->avctx->debug & FF_DEBUG_MMCO)
+            av_log(h->avctx, AV_LOG_DEBUG, "mmco:%d %d %d\n", h->mmco[i].opcode,
+                   h->mmco[i].short_pic_num, h->mmco[i].long_arg);
+
+        if (mmco[i].opcode == MMCO_SHORT2UNUSED ||
+            mmco[i].opcode == MMCO_SHORT2LONG) {
+            frame_num = pic_num_extract(h, mmco[i].short_pic_num, &structure);
+            pic       = find_short(h, frame_num, &j);
+            if (!pic) {
+                if (mmco[i].opcode != MMCO_SHORT2LONG ||
+                    !h->long_ref[mmco[i].long_arg]    ||
+                    h->long_ref[mmco[i].long_arg]->frame_num != frame_num) {
+                    av_log(h->avctx, AV_LOG_ERROR, "mmco: unref short failure\n");
+                    err = AVERROR_INVALIDDATA;
+                }
+                continue;
+            }
+        }
+
+        switch (mmco[i].opcode) {
+        case MMCO_SHORT2UNUSED:
+            if (h->avctx->debug & FF_DEBUG_MMCO)
+                av_log(h->avctx, AV_LOG_DEBUG, "mmco: unref short %d count %d\n",
+                       h->mmco[i].short_pic_num, h->short_ref_count);
+            remove_short(h, frame_num, structure ^ PICT_FRAME);
+            break;
+        case MMCO_SHORT2LONG:
+                if (h->long_ref[mmco[i].long_arg] != pic)
+                    remove_long(h, mmco[i].long_arg, 0);
+
+                remove_short_at_index(h, j);
+                h->long_ref[ mmco[i].long_arg ] = pic;
+                if (h->long_ref[mmco[i].long_arg]) {
+                    h->long_ref[mmco[i].long_arg]->long_ref = 1;
+                    h->long_ref_count++;
+                }
+            break;
+        case MMCO_LONG2UNUSED:
+            j   = pic_num_extract(h, mmco[i].long_arg, &structure);
+            pic = h->long_ref[j];
+            if (pic) {
+                remove_long(h, j, structure ^ PICT_FRAME);
+            } else if (h->avctx->debug & FF_DEBUG_MMCO)
+                av_log(h->avctx, AV_LOG_DEBUG, "mmco: unref long failure\n");
+            break;
+        case MMCO_LONG:
+                    // Comment below left from previous code as it is an interresting note.
+                    /* First field in pair is in short term list or
+                     * at a different long term index.
+                     * This is not allowed; see 7.4.3.3, notes 2 and 3.
+                     * Report the problem and keep the pair where it is,
+                     * and mark this field valid.
+                     */
+
+            if (h->long_ref[mmco[i].long_arg] != h->cur_pic_ptr) {
+                remove_long(h, mmco[i].long_arg, 0);
+
+                h->long_ref[mmco[i].long_arg]           = h->cur_pic_ptr;
+                h->long_ref[mmco[i].long_arg]->long_ref = 1;
+                h->long_ref_count++;
+            }
+
+            h->cur_pic_ptr->reference |= h->picture_structure;
+            current_ref_assigned = 1;
+            break;
+        case MMCO_SET_MAX_LONG:
+            assert(mmco[i].long_arg <= 16);
+            // just remove the long term which index is greater than new max
+            for (j = mmco[i].long_arg; j < 16; j++) {
+                remove_long(h, j, 0);
+            }
+            break;
+        case MMCO_RESET:
+            while (h->short_ref_count) {
+                remove_short(h, h->short_ref[0]->frame_num, 0);
+            }
+            for (j = 0; j < 16; j++) {
+                remove_long(h, j, 0);
+            }
+            h->frame_num  = h->cur_pic_ptr->frame_num = 0;
+            h->mmco_reset = 1;
+            h->cur_pic_ptr->mmco_reset = 1;
+            for (j = 0; j < MAX_DELAYED_PIC_COUNT; j++)
+                h->last_pocs[j] = INT_MIN;
+            break;
+        default: assert(0);
+        }
+    }
+
+    if (!current_ref_assigned) {
+        /* Second field of complementary field pair; the first field of
+         * which is already referenced. If short referenced, it
+         * should be first entry in short_ref. If not, it must exist
+         * in long_ref; trying to put it on the short list here is an
+         * error in the encoded bit stream (ref: 7.4.3.3, NOTE 2 and 3).
+         */
+        if (h->short_ref_count && h->short_ref[0] == h->cur_pic_ptr) {
+            /* Just mark the second field valid */
+            h->cur_pic_ptr->reference = PICT_FRAME;
+        } else if (h->cur_pic_ptr->long_ref) {
+            av_log(h->avctx, AV_LOG_ERROR, "illegal short term reference "
+                                           "assignment for second field "
+                                           "in complementary field pair "
+                                           "(first field is long term)\n");
+            err = AVERROR_INVALIDDATA;
+        } else {
+            pic = remove_short(h, h->cur_pic_ptr->frame_num, 0);
+            if (pic) {
+                av_log(h->avctx, AV_LOG_ERROR, "illegal short term buffer state detected\n");
+                err = AVERROR_INVALIDDATA;
+            }
+
+            if (h->short_ref_count)
+                memmove(&h->short_ref[1], &h->short_ref[0],
+                        h->short_ref_count * sizeof(Picture*));
+
+            h->short_ref[0] = h->cur_pic_ptr;
+            h->short_ref_count++;
+            h->cur_pic_ptr->reference |= h->picture_structure;
+        }
+    }
+
+    if (h->long_ref_count + h->short_ref_count > FFMAX(h->sps.ref_frame_count, 1)) {
+
+        /* We have too many reference frames, probably due to corrupted
+         * stream. Need to discard one frame. Prevents overrun of the
+         * short_ref and long_ref buffers.
+         */
+        av_log(h->avctx, AV_LOG_ERROR,
+               "number of reference frames (%d+%d) exceeds max (%d; probably "
+               "corrupt input), discarding one\n",
+               h->long_ref_count, h->short_ref_count, h->sps.ref_frame_count);
+        err = AVERROR_INVALIDDATA;
+
+        if (h->long_ref_count && !h->short_ref_count) {
+            for (i = 0; i < 16; ++i)
+                if (h->long_ref[i])
+                    break;
+
+            assert(i < 16);
+            remove_long(h, i, 0);
+        } else {
+            pic = h->short_ref[h->short_ref_count - 1];
+            remove_short(h, pic->frame_num, 0);
+        }
+    }
+
+    print_short_term(h);
+    print_long_term(h);
+
+    if(err >= 0 && h->long_ref_count==0 && h->short_ref_count<=2 && h->pps.ref_count[0]<=1 + (h->picture_structure != PICT_FRAME) && h->cur_pic_ptr->f.pict_type == AV_PICTURE_TYPE_I){
+        h->cur_pic_ptr->sync |= 1;
+        if(!h->avctx->has_b_frames)
+            h->sync = 2;
+    }
+
+    return (h->avctx->err_recognition & AV_EF_EXPLODE) ? err : 0;
+}
+
+int ff_h264_decode_ref_pic_marking(H264Context *h, GetBitContext *gb,
+                                   int first_slice)
+{
+    int i, ret;
+    MMCO mmco_temp[MAX_MMCO_COUNT], *mmco = first_slice ? h->mmco : mmco_temp;
+    int mmco_index = 0;
+
+    if (h->nal_unit_type == NAL_IDR_SLICE) { // FIXME fields
+        skip_bits1(gb); // broken_link
+        if (get_bits1(gb)) {
+            mmco[0].opcode   = MMCO_LONG;
+            mmco[0].long_arg = 0;
+            mmco_index       = 1;
+        }
+    } else {
+        if (get_bits1(gb)) { // adaptive_ref_pic_marking_mode_flag
+            for (i = 0; i < MAX_MMCO_COUNT; i++) {
+                MMCOOpcode opcode = get_ue_golomb_31(gb);
+
+                mmco[i].opcode = opcode;
+                if (opcode == MMCO_SHORT2UNUSED || opcode == MMCO_SHORT2LONG) {
+                    mmco[i].short_pic_num =
+                        (h->curr_pic_num - get_ue_golomb(gb) - 1) &
+                            (h->max_pic_num - 1);
+#if 0
+                    if (mmco[i].short_pic_num >= h->short_ref_count ||
+                        h->short_ref[ mmco[i].short_pic_num ] == NULL){
+                        av_log(s->avctx, AV_LOG_ERROR,
+                               "illegal short ref in memory management control "
+                               "operation %d\n", mmco);
+                        return -1;
+                    }
+#endif
+                }
+                if (opcode == MMCO_SHORT2LONG || opcode == MMCO_LONG2UNUSED ||
+                    opcode == MMCO_LONG || opcode == MMCO_SET_MAX_LONG) {
+                    unsigned int long_arg = get_ue_golomb_31(gb);
+                    if (long_arg >= 32 ||
+                        (long_arg >= 16 && !(opcode == MMCO_SET_MAX_LONG &&
+                                             long_arg == 16) &&
+                         !(opcode == MMCO_LONG2UNUSED && FIELD_PICTURE(h)))) {
+                        av_log(h->avctx, AV_LOG_ERROR,
+                               "illegal long ref in memory management control "
+                               "operation %d\n", opcode);
+                        return -1;
+                    }
+                    mmco[i].long_arg = long_arg;
+                }
+
+                if (opcode > (unsigned) MMCO_LONG) {
+                    av_log(h->avctx, AV_LOG_ERROR,
+                           "illegal memory management control operation %d\n",
+                           opcode);
+                    return -1;
+                }
+                if (opcode == MMCO_END)
+                    break;
+            }
+            mmco_index = i;
+        } else {
+            if (first_slice) {
+                ret = ff_generate_sliding_window_mmcos(h, first_slice);
+                if (ret < 0 && h->avctx->err_recognition & AV_EF_EXPLODE)
+                    return ret;
+            }
+            mmco_index = -1;
+        }
+    }
+
+    if (first_slice && mmco_index != -1) {
+        h->mmco_index = mmco_index;
+    } else if (!first_slice && mmco_index >= 0 &&
+               (mmco_index != h->mmco_index ||
+                (i = check_opcodes(h->mmco, mmco_temp, mmco_index)))) {
+        av_log(h->avctx, AV_LOG_ERROR,
+               "Inconsistent MMCO state between slices [%d, %d]\n",
+               mmco_index, h->mmco_index);
+        return AVERROR_INVALIDDATA;
+    }
+
+    return 0;
+}