chasing indexing error

1 files changed, 0 insertions, 850 deletions

diff --git a/ffmpeg/libavcodec/mss2.c b/ffmpeg/libavcodec/mss2.c
deleted file mode 100644
index 99db046..0000000
--- a/ffmpeg/libavcodec/mss2.c
+++ /dev/null
@@ -1,850 +0,0 @@
-/*
- * Microsoft Screen 2 (aka Windows Media Video V9 Screen) decoder
- *
- * 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
- * Microsoft Screen 2 (aka Windows Media Video V9 Screen) decoder
- */
-
-#include "libavutil/avassert.h"
-#include "error_resilience.h"
-#include "internal.h"
-#include "msmpeg4data.h"
-#include "vc1.h"
-#include "mss12.h"
-#include "mss2dsp.h"
-
-typedef struct MSS2Context {
-    VC1Context     v;
-    int            split_position;
-    AVFrame       *last_pic;
-    MSS12Context   c;
-    MSS2DSPContext dsp;
-    SliceContext   sc[2];
-} MSS2Context;
-
-static void arith2_normalise(ArithCoder *c)
-{
-    while ((c->high >> 15) - (c->low >> 15) < 2) {
-        if ((c->low ^ c->high) & 0x10000) {
-            c->high  ^= 0x8000;
-            c->value ^= 0x8000;
-            c->low   ^= 0x8000;
-        }
-        c->high  = c->high  << 8 & 0xFFFFFF | 0xFF;
-        c->value = c->value << 8 & 0xFFFFFF | bytestream2_get_byte(c->gbc.gB);
-        c->low   = c->low   << 8 & 0xFFFFFF;
-    }
-}
-
-ARITH_GET_BIT(2)
-
-/* L. Stuiver and A. Moffat: "Piecewise Integer Mapping for Arithmetic Coding."
- * In Proc. 8th Data Compression Conference (DCC '98), pp. 3-12, Mar. 1998 */
-
-static int arith2_get_scaled_value(int value, int n, int range)
-{
-    int split = (n << 1) - range;
-
-    if (value > split)
-        return split + (value - split >> 1);
-    else
-        return value;
-}
-
-static void arith2_rescale_interval(ArithCoder *c, int range,
-                                    int low, int high, int n)
-{
-    int split = (n << 1) - range;
-
-    if (high > split)
-        c->high = split + (high - split << 1);
-    else
-        c->high = high;
-
-    c->high += c->low - 1;
-
-    if (low > split)
-        c->low += split + (low - split << 1);
-    else
-        c->low += low;
-}
-
-static int arith2_get_number(ArithCoder *c, int n)
-{
-    int range = c->high - c->low + 1;
-    int scale = av_log2(range) - av_log2(n);
-    int val;
-
-    if (n << scale > range)
-        scale--;
-
-    n <<= scale;
-
-    val = arith2_get_scaled_value(c->value - c->low, n, range) >> scale;
-
-    arith2_rescale_interval(c, range, val << scale, (val + 1) << scale, n);
-
-    arith2_normalise(c);
-
-    return val;
-}
-
-static int arith2_get_prob(ArithCoder *c, int16_t *probs)
-{
-    int range = c->high - c->low + 1, n = *probs;
-    int scale = av_log2(range) - av_log2(n);
-    int i     = 0, val;
-
-    if (n << scale > range)
-        scale--;
-
-    n <<= scale;
-
-    val = arith2_get_scaled_value(c->value - c->low, n, range) >> scale;
-    while (probs[++i] > val) ;
-
-    arith2_rescale_interval(c, range,
-                            probs[i] << scale, probs[i - 1] << scale, n);
-
-    return i;
-}
-
-ARITH_GET_MODEL_SYM(2)
-
-static int arith2_get_consumed_bytes(ArithCoder *c)
-{
-    int diff = (c->high >> 16) - (c->low >> 16);
-    int bp   = bytestream2_tell(c->gbc.gB) - 3 << 3;
-    int bits = 1;
-
-    while (!(diff & 0x80)) {
-        bits++;
-        diff <<= 1;
-    }
-
-    return (bits + bp + 7 >> 3) + ((c->low >> 16) + 1 == c->high >> 16);
-}
-
-static void arith2_init(ArithCoder *c, GetByteContext *gB)
-{
-    c->low           = 0;
-    c->high          = 0xFFFFFF;
-    c->value         = bytestream2_get_be24(gB);
-    c->gbc.gB        = gB;
-    c->get_model_sym = arith2_get_model_sym;
-    c->get_number    = arith2_get_number;
-}
-
-static int decode_pal_v2(MSS12Context *ctx, const uint8_t *buf, int buf_size)
-{
-    int i, ncol;
-    uint32_t *pal = ctx->pal + 256 - ctx->free_colours;
-
-    if (!ctx->free_colours)
-        return 0;
-
-    ncol = *buf++;
-    if (ncol > ctx->free_colours || buf_size < 2 + ncol * 3)
-        return AVERROR_INVALIDDATA;
-    for (i = 0; i < ncol; i++)
-        *pal++ = AV_RB24(buf + 3 * i);
-
-    return 1 + ncol * 3;
-}
-
-static int decode_555(GetByteContext *gB, uint16_t *dst, int stride,
-                      int keyframe, int w, int h)
-{
-    int last_symbol = 0, repeat = 0, prev_avail = 0;
-
-    if (!keyframe) {
-        int x, y, endx, endy, t;
-
-#define READ_PAIR(a, b)                 \
-    a  = bytestream2_get_byte(gB) << 4; \
-    t  = bytestream2_get_byte(gB);      \
-    a |= t >> 4;                        \
-    b  = (t & 0xF) << 8;                \
-    b |= bytestream2_get_byte(gB);      \
-
-        READ_PAIR(x, endx)
-        READ_PAIR(y, endy)
-
-        if (endx >= w || endy >= h || x > endx || y > endy)
-            return AVERROR_INVALIDDATA;
-        dst += x + stride * y;
-        w    = endx - x + 1;
-        h    = endy - y + 1;
-        if (y)
-            prev_avail = 1;
-    }
-
-    do {
-        uint16_t *p = dst;
-        do {
-            if (repeat-- < 1) {
-                int b = bytestream2_get_byte(gB);
-                if (b < 128)
-                    last_symbol = b << 8 | bytestream2_get_byte(gB);
-                else if (b > 129) {
-                    repeat = 0;
-                    while (b-- > 130)
-                        repeat = (repeat << 8) + bytestream2_get_byte(gB) + 1;
-                    if (last_symbol == -2) {
-                        int skip = FFMIN((unsigned)repeat, dst + w - p);
-                        repeat -= skip;
-                        p      += skip;
-                    }
-                } else
-                    last_symbol = 127 - b;
-            }
-            if (last_symbol >= 0)
-                *p = last_symbol;
-            else if (last_symbol == -1 && prev_avail)
-                *p = *(p - stride);
-        } while (++p < dst + w);
-        dst       += stride;
-        prev_avail = 1;
-    } while (--h);
-
-    return 0;
-}
-
-static int decode_rle(GetBitContext *gb, uint8_t *pal_dst, int pal_stride,
-                      uint8_t *rgb_dst, int rgb_stride, uint32_t *pal,
-                      int keyframe, int kf_slipt, int slice, int w, int h)
-{
-    uint8_t bits[270] = { 0 };
-    uint32_t codes[270];
-    VLC vlc;
-
-    int current_length = 0, read_codes = 0, next_code = 0, current_codes = 0;
-    int remaining_codes, surplus_codes, i;
-
-    const int alphabet_size = 270 - keyframe;
-
-    int last_symbol = 0, repeat = 0, prev_avail = 0;
-
-    if (!keyframe) {
-        int x, y, clipw, cliph;
-
-        x     = get_bits(gb, 12);
-        y     = get_bits(gb, 12);
-        clipw = get_bits(gb, 12) + 1;
-        cliph = get_bits(gb, 12) + 1;
-
-        if (x + clipw > w || y + cliph > h)
-            return AVERROR_INVALIDDATA;
-        pal_dst += pal_stride * y + x;
-        rgb_dst += rgb_stride * y + x * 3;
-        w        = clipw;
-        h        = cliph;
-        if (y)
-            prev_avail = 1;
-    } else {
-        if (slice > 0) {
-            pal_dst   += pal_stride * kf_slipt;
-            rgb_dst   += rgb_stride * kf_slipt;
-            prev_avail = 1;
-            h         -= kf_slipt;
-        } else
-            h = kf_slipt;
-    }
-
-    /* read explicit codes */
-    do {
-        while (current_codes--) {
-            int symbol = get_bits(gb, 8);
-            if (symbol >= 204 - keyframe)
-                symbol += 14 - keyframe;
-            else if (symbol > 189)
-                symbol = get_bits1(gb) + (symbol << 1) - 190;
-            if (bits[symbol])
-                return AVERROR_INVALIDDATA;
-            bits[symbol]  = current_length;
-            codes[symbol] = next_code++;
-            read_codes++;
-        }
-        current_length++;
-        next_code     <<= 1;
-        remaining_codes = (1 << current_length) - next_code;
-        current_codes   = get_bits(gb, av_ceil_log2(remaining_codes + 1));
-        if (current_length > 22 || current_codes > remaining_codes)
-            return AVERROR_INVALIDDATA;
-    } while (current_codes != remaining_codes);
-
-    remaining_codes = alphabet_size - read_codes;
-
-    /* determine the minimum length to fit the rest of the alphabet */
-    while ((surplus_codes = (2 << current_length) -
-                            (next_code << 1) - remaining_codes) < 0) {
-        current_length++;
-        next_code <<= 1;
-    }
-
-    /* add the rest of the symbols lexicographically */
-    for (i = 0; i < alphabet_size; i++)
-        if (!bits[i]) {
-            if (surplus_codes-- == 0) {
-                current_length++;
-                next_code <<= 1;
-            }
-            bits[i]  = current_length;
-            codes[i] = next_code++;
-        }
-
-    if (next_code != 1 << current_length)
-        return AVERROR_INVALIDDATA;
-
-    if (i = init_vlc(&vlc, 9, alphabet_size, bits, 1, 1, codes, 4, 4, 0))
-        return i;
-
-    /* frame decode */
-    do {
-        uint8_t *pp = pal_dst;
-        uint8_t *rp = rgb_dst;
-        do {
-            if (repeat-- < 1) {
-                int b = get_vlc2(gb, vlc.table, 9, 3);
-                if (b < 256)
-                    last_symbol = b;
-                else if (b < 268) {
-                    b -= 256;
-                    if (b == 11)
-                        b = get_bits(gb, 4) + 10;
-
-                    if (!b)
-                        repeat = 0;
-                    else
-                        repeat = get_bits(gb, b);
-
-                    repeat += (1 << b) - 1;
-
-                    if (last_symbol == -2) {
-                        int skip = FFMIN(repeat, pal_dst + w - pp);
-                        repeat -= skip;
-                        pp     += skip;
-                        rp     += skip * 3;
-                    }
-                } else
-                    last_symbol = 267 - b;
-            }
-            if (last_symbol >= 0) {
-                *pp = last_symbol;
-                AV_WB24(rp, pal[last_symbol]);
-            } else if (last_symbol == -1 && prev_avail) {
-                *pp = *(pp - pal_stride);
-                memcpy(rp, rp - rgb_stride, 3);
-            }
-            rp += 3;
-        } while (++pp < pal_dst + w);
-        pal_dst   += pal_stride;
-        rgb_dst   += rgb_stride;
-        prev_avail = 1;
-    } while (--h);
-
-    ff_free_vlc(&vlc);
-    return 0;
-}
-
-static int decode_wmv9(AVCodecContext *avctx, const uint8_t *buf, int buf_size,
-                       int x, int y, int w, int h, int wmv9_mask)
-{
-    MSS2Context *ctx  = avctx->priv_data;
-    MSS12Context *c   = &ctx->c;
-    VC1Context *v     = avctx->priv_data;
-    MpegEncContext *s = &v->s;
-    AVFrame *f;
-    int ret;
-
-    ff_mpeg_flush(avctx);
-
-    if ((ret = init_get_bits8(&s->gb, buf, buf_size)) < 0)
-        return ret;
-
-    s->loop_filter = avctx->skip_loop_filter < AVDISCARD_ALL;
-
-    if (ff_vc1_parse_frame_header(v, &s->gb) < 0) {
-        av_log(v->s.avctx, AV_LOG_ERROR, "header error\n");
-        return AVERROR_INVALIDDATA;
-    }
-
-    if (s->pict_type != AV_PICTURE_TYPE_I) {
-        av_log(v->s.avctx, AV_LOG_ERROR, "expected I-frame\n");
-        return AVERROR_INVALIDDATA;
-    }
-
-    avctx->pix_fmt = AV_PIX_FMT_YUV420P;
-
-    if ((ret = ff_MPV_frame_start(s, avctx)) < 0) {
-        av_log(v->s.avctx, AV_LOG_ERROR, "ff_MPV_frame_start error\n");
-        avctx->pix_fmt = AV_PIX_FMT_RGB24;
-        return ret;
-    }
-
-    ff_mpeg_er_frame_start(s);
-
-    v->bits = buf_size * 8;
-
-    v->end_mb_x = (w + 15) >> 4;
-    s->end_mb_y = (h + 15) >> 4;
-    if (v->respic & 1)
-        v->end_mb_x = v->end_mb_x + 1 >> 1;
-    if (v->respic & 2)
-        s->end_mb_y = s->end_mb_y + 1 >> 1;
-
-    ff_vc1_decode_blocks(v);
-
-    ff_er_frame_end(&s->er);
-
-    ff_MPV_frame_end(s);
-
-    f = &s->current_picture.f;
-
-    if (v->respic == 3) {
-        ctx->dsp.upsample_plane(f->data[0], f->linesize[0], w,      h);
-        ctx->dsp.upsample_plane(f->data[1], f->linesize[1], w >> 1, h >> 1);
-        ctx->dsp.upsample_plane(f->data[2], f->linesize[2], w >> 1, h >> 1);
-    } else if (v->respic)
-        avpriv_request_sample(v->s.avctx,
-                              "Asymmetric WMV9 rectangle subsampling");
-
-    av_assert0(f->linesize[1] == f->linesize[2]);
-
-    if (wmv9_mask != -1)
-        ctx->dsp.mss2_blit_wmv9_masked(c->rgb_pic + y * c->rgb_stride + x * 3,
-                                       c->rgb_stride, wmv9_mask,
-                                       c->pal_pic + y * c->pal_stride + x,
-                                       c->pal_stride,
-                                       f->data[0], f->linesize[0],
-                                       f->data[1], f->data[2], f->linesize[1],
-                                       w, h);
-    else
-        ctx->dsp.mss2_blit_wmv9(c->rgb_pic + y * c->rgb_stride + x * 3,
-                                c->rgb_stride,
-                                f->data[0], f->linesize[0],
-                                f->data[1], f->data[2], f->linesize[1],
-                                w, h);
-
-    avctx->pix_fmt = AV_PIX_FMT_RGB24;
-
-    return 0;
-}
-
-typedef struct Rectangle {
-    int coded, x, y, w, h;
-} Rectangle;
-
-#define MAX_WMV9_RECTANGLES 20
-#define ARITH2_PADDING 2
-
-static int mss2_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
-                             AVPacket *avpkt)
-{
-    const uint8_t *buf = avpkt->data;
-    int buf_size       = avpkt->size;
-    MSS2Context *ctx = avctx->priv_data;
-    MSS12Context *c  = &ctx->c;
-    AVFrame *frame   = data;
-    GetBitContext gb;
-    GetByteContext gB;
-    ArithCoder acoder;
-
-    int keyframe, has_wmv9, has_mv, is_rle, is_555, ret;
-
-    Rectangle wmv9rects[MAX_WMV9_RECTANGLES], *r;
-    int used_rects = 0, i, implicit_rect = 0, av_uninit(wmv9_mask);
-
-    av_assert0(FF_INPUT_BUFFER_PADDING_SIZE >=
-               ARITH2_PADDING + (MIN_CACHE_BITS + 7) / 8);
-
-    if ((ret = init_get_bits8(&gb, buf, buf_size)) < 0)
-        return ret;
-
-    if (keyframe = get_bits1(&gb))
-        skip_bits(&gb, 7);
-    has_wmv9 = get_bits1(&gb);
-    has_mv   = keyframe ? 0 : get_bits1(&gb);
-    is_rle   = get_bits1(&gb);
-    is_555   = is_rle && get_bits1(&gb);
-    if (c->slice_split > 0)
-        ctx->split_position = c->slice_split;
-    else if (c->slice_split < 0) {
-        if (get_bits1(&gb)) {
-            if (get_bits1(&gb)) {
-                if (get_bits1(&gb))
-                    ctx->split_position = get_bits(&gb, 16);
-                else
-                    ctx->split_position = get_bits(&gb, 12);
-            } else
-                ctx->split_position = get_bits(&gb, 8) << 4;
-        } else {
-            if (keyframe)
-                ctx->split_position = avctx->height / 2;
-        }
-    } else
-        ctx->split_position = avctx->height;
-
-    if (c->slice_split && (ctx->split_position < 1 - is_555 ||
-                           ctx->split_position > avctx->height - 1))
-        return AVERROR_INVALIDDATA;
-
-    align_get_bits(&gb);
-    buf      += get_bits_count(&gb) >> 3;
-    buf_size -= get_bits_count(&gb) >> 3;
-
-    if (buf_size < 1)
-        return AVERROR_INVALIDDATA;
-
-    if (is_555 && (has_wmv9 || has_mv || c->slice_split && ctx->split_position))
-        return AVERROR_INVALIDDATA;
-
-    avctx->pix_fmt = is_555 ? AV_PIX_FMT_RGB555 : AV_PIX_FMT_RGB24;
-    if (ctx->last_pic->format != avctx->pix_fmt)
-        av_frame_unref(ctx->last_pic);
-
-    if (has_wmv9) {
-        bytestream2_init(&gB, buf, buf_size + ARITH2_PADDING);
-        arith2_init(&acoder, &gB);
-
-        implicit_rect = !arith2_get_bit(&acoder);
-
-        while (arith2_get_bit(&acoder)) {
-            if (used_rects == MAX_WMV9_RECTANGLES)
-                return AVERROR_INVALIDDATA;
-            r = &wmv9rects[used_rects];
-            if (!used_rects)
-                r->x = arith2_get_number(&acoder, avctx->width);
-            else
-                r->x = arith2_get_number(&acoder, avctx->width -
-                                         wmv9rects[used_rects - 1].x) +
-                       wmv9rects[used_rects - 1].x;
-            r->y = arith2_get_number(&acoder, avctx->height);
-            r->w = arith2_get_number(&acoder, avctx->width  - r->x) + 1;
-            r->h = arith2_get_number(&acoder, avctx->height - r->y) + 1;
-            used_rects++;
-        }
-
-        if (implicit_rect && used_rects) {
-            av_log(avctx, AV_LOG_ERROR, "implicit_rect && used_rects > 0\n");
-            return AVERROR_INVALIDDATA;
-        }
-
-        if (implicit_rect) {
-            wmv9rects[0].x = 0;
-            wmv9rects[0].y = 0;
-            wmv9rects[0].w = avctx->width;
-            wmv9rects[0].h = avctx->height;
-
-            used_rects = 1;
-        }
-        for (i = 0; i < used_rects; i++) {
-            if (!implicit_rect && arith2_get_bit(&acoder)) {
-                av_log(avctx, AV_LOG_ERROR, "Unexpected grandchildren\n");
-                return AVERROR_INVALIDDATA;
-            }
-            if (!i) {
-                wmv9_mask = arith2_get_bit(&acoder) - 1;
-                if (!wmv9_mask)
-                    wmv9_mask = arith2_get_number(&acoder, 256);
-            }
-            wmv9rects[i].coded = arith2_get_number(&acoder, 2);
-        }
-
-        buf      += arith2_get_consumed_bytes(&acoder);
-        buf_size -= arith2_get_consumed_bytes(&acoder);
-        if (buf_size < 1)
-            return AVERROR_INVALIDDATA;
-    }
-
-    c->mvX = c->mvY = 0;
-    if (keyframe && !is_555) {
-        if ((i = decode_pal_v2(c, buf, buf_size)) < 0)
-            return AVERROR_INVALIDDATA;
-        buf      += i;
-        buf_size -= i;
-    } else if (has_mv) {
-        buf      += 4;
-        buf_size -= 4;
-        if (buf_size < 1)
-            return AVERROR_INVALIDDATA;
-        c->mvX = AV_RB16(buf - 4) - avctx->width;
-        c->mvY = AV_RB16(buf - 2) - avctx->height;
-    }
-
-    if (c->mvX < 0 || c->mvY < 0) {
-        FFSWAP(uint8_t *, c->pal_pic, c->last_pal_pic);
-
-        if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0)
-            return ret;
-
-        if (ctx->last_pic->data[0]) {
-            av_assert0(frame->linesize[0] == ctx->last_pic->linesize[0]);
-            c->last_rgb_pic = ctx->last_pic->data[0] +
-                              ctx->last_pic->linesize[0] * (avctx->height - 1);
-        } else {
-            av_log(avctx, AV_LOG_ERROR, "Missing keyframe\n");
-            return AVERROR_INVALIDDATA;
-        }
-    } else {
-        if ((ret = ff_reget_buffer(avctx, ctx->last_pic)) < 0)
-            return ret;
-        if ((ret = av_frame_ref(frame, ctx->last_pic)) < 0)
-            return ret;
-
-        c->last_rgb_pic = NULL;
-    }
-    c->rgb_pic    = frame->data[0] +
-                    frame->linesize[0] * (avctx->height - 1);
-    c->rgb_stride = -frame->linesize[0];
-
-    frame->key_frame = keyframe;
-    frame->pict_type = keyframe ? AV_PICTURE_TYPE_I : AV_PICTURE_TYPE_P;
-
-    if (is_555) {
-        bytestream2_init(&gB, buf, buf_size);
-
-        if (decode_555(&gB, (uint16_t *)c->rgb_pic, c->rgb_stride >> 1,
-                       keyframe, avctx->width, avctx->height))
-            return AVERROR_INVALIDDATA;
-
-        buf_size -= bytestream2_tell(&gB);
-    } else {
-        if (keyframe) {
-            c->corrupted = 0;
-            ff_mss12_slicecontext_reset(&ctx->sc[0]);
-            if (c->slice_split)
-                ff_mss12_slicecontext_reset(&ctx->sc[1]);
-        }
-        if (is_rle) {
-            if ((ret = init_get_bits8(&gb, buf, buf_size)) < 0)
-                return ret;
-            if (ret = decode_rle(&gb, c->pal_pic, c->pal_stride,
-                                 c->rgb_pic, c->rgb_stride, c->pal, keyframe,
-                                 ctx->split_position, 0,
-                                 avctx->width, avctx->height))
-                return ret;
-            align_get_bits(&gb);
-
-            if (c->slice_split)
-                if (ret = decode_rle(&gb, c->pal_pic, c->pal_stride,
-                                     c->rgb_pic, c->rgb_stride, c->pal, keyframe,
-                                     ctx->split_position, 1,
-                                     avctx->width, avctx->height))
-                    return ret;
-
-            align_get_bits(&gb);
-            buf      += get_bits_count(&gb) >> 3;
-            buf_size -= get_bits_count(&gb) >> 3;
-        } else if (!implicit_rect || wmv9_mask != -1) {
-            if (c->corrupted)
-                return AVERROR_INVALIDDATA;
-            bytestream2_init(&gB, buf, buf_size + ARITH2_PADDING);
-            arith2_init(&acoder, &gB);
-            c->keyframe = keyframe;
-            if (c->corrupted = ff_mss12_decode_rect(&ctx->sc[0], &acoder, 0, 0,
-                                                    avctx->width,
-                                                    ctx->split_position))
-                return AVERROR_INVALIDDATA;
-
-            buf      += arith2_get_consumed_bytes(&acoder);
-            buf_size -= arith2_get_consumed_bytes(&acoder);
-            if (c->slice_split) {
-                if (buf_size < 1)
-                    return AVERROR_INVALIDDATA;
-                bytestream2_init(&gB, buf, buf_size + ARITH2_PADDING);
-                arith2_init(&acoder, &gB);
-                if (c->corrupted = ff_mss12_decode_rect(&ctx->sc[1], &acoder, 0,
-                                                        ctx->split_position,
-                                                        avctx->width,
-                                                        avctx->height - ctx->split_position))
-                    return AVERROR_INVALIDDATA;
-
-                buf      += arith2_get_consumed_bytes(&acoder);
-                buf_size -= arith2_get_consumed_bytes(&acoder);
-            }
-        } else
-            memset(c->pal_pic, 0, c->pal_stride * avctx->height);
-    }
-
-    if (has_wmv9) {
-        for (i = 0; i < used_rects; i++) {
-            int x = wmv9rects[i].x;
-            int y = wmv9rects[i].y;
-            int w = wmv9rects[i].w;
-            int h = wmv9rects[i].h;
-            if (wmv9rects[i].coded) {
-                int WMV9codedFrameSize;
-                if (buf_size < 4 || !(WMV9codedFrameSize = AV_RL24(buf)))
-                    return AVERROR_INVALIDDATA;
-                if (ret = decode_wmv9(avctx, buf + 3, buf_size - 3,
-                                      x, y, w, h, wmv9_mask))
-                    return ret;
-                buf      += WMV9codedFrameSize + 3;
-                buf_size -= WMV9codedFrameSize + 3;
-            } else {
-                uint8_t *dst = c->rgb_pic + y * c->rgb_stride + x * 3;
-                if (wmv9_mask != -1) {
-                    ctx->dsp.mss2_gray_fill_masked(dst, c->rgb_stride,
-                                                   wmv9_mask,
-                                                   c->pal_pic + y * c->pal_stride + x,
-                                                   c->pal_stride,
-                                                   w, h);
-                } else {
-                    do {
-                        memset(dst, 0x80, w * 3);
-                        dst += c->rgb_stride;
-                    } while (--h);
-                }
-            }
-        }
-    }
-
-    if (buf_size)
-        av_log(avctx, AV_LOG_WARNING, "buffer not fully consumed\n");
-
-    if (c->mvX < 0 || c->mvY < 0) {
-        av_frame_unref(ctx->last_pic);
-        ret = av_frame_ref(ctx->last_pic, frame);
-        if (ret < 0)
-            return ret;
-    }
-
-    *got_frame       = 1;
-
-    return avpkt->size;
-}
-
-static av_cold int wmv9_init(AVCodecContext *avctx)
-{
-    VC1Context *v = avctx->priv_data;
-    int ret;
-
-    v->s.avctx    = avctx;
-    avctx->flags |= CODEC_FLAG_EMU_EDGE;
-    v->s.flags   |= CODEC_FLAG_EMU_EDGE;
-
-    if ((ret = ff_vc1_init_common(v)) < 0)
-        return ret;
-    ff_vc1dsp_init(&v->vc1dsp);
-
-    v->profile = PROFILE_MAIN;
-
-    v->zz_8x4     = ff_wmv2_scantableA;
-    v->zz_4x8     = ff_wmv2_scantableB;
-    v->res_y411   = 0;
-    v->res_sprite = 0;
-
-    v->frmrtq_postproc = 7;
-    v->bitrtq_postproc = 31;
-
-    v->res_x8          = 0;
-    v->multires        = 0;
-    v->res_fasttx      = 1;
-
-    v->fastuvmc        = 0;
-
-    v->extended_mv     = 0;
-
-    v->dquant          = 1;
-    v->vstransform     = 1;
-
-    v->res_transtab    = 0;
-
-    v->overlap         = 0;
-
-    v->resync_marker   = 0;
-    v->rangered        = 0;
-
-    v->s.max_b_frames = avctx->max_b_frames = 0;
-    v->quantizer_mode = 0;
-
-    v->finterpflag = 0;
-
-    v->res_rtm_flag = 1;
-
-    ff_vc1_init_transposed_scantables(v);
-
-    if ((ret = ff_msmpeg4_decode_init(avctx)) < 0 ||
-        (ret = ff_vc1_decode_init_alloc_tables(v)) < 0)
-        return ret;
-
-    /* error concealment */
-    v->s.me.qpel_put = v->s.dsp.put_qpel_pixels_tab;
-    v->s.me.qpel_avg = v->s.dsp.avg_qpel_pixels_tab;
-
-    return 0;
-}
-
-static av_cold int mss2_decode_end(AVCodecContext *avctx)
-{
-    MSS2Context *const ctx = avctx->priv_data;
-
-    av_frame_free(&ctx->last_pic);
-
-    ff_mss12_decode_end(&ctx->c);
-    av_freep(&ctx->c.pal_pic);
-    av_freep(&ctx->c.last_pal_pic);
-    ff_vc1_decode_end(avctx);
-
-    return 0;
-}
-
-static av_cold int mss2_decode_init(AVCodecContext *avctx)
-{
-    MSS2Context * const ctx = avctx->priv_data;
-    MSS12Context *c = &ctx->c;
-    int ret;
-    c->avctx = avctx;
-    if (ret = ff_mss12_decode_init(c, 1, &ctx->sc[0], &ctx->sc[1]))
-        return ret;
-    ctx->last_pic   = av_frame_alloc();
-    c->pal_stride   = c->mask_stride;
-    c->pal_pic      = av_mallocz(c->pal_stride * avctx->height);
-    c->last_pal_pic = av_mallocz(c->pal_stride * avctx->height);
-    if (!c->pal_pic || !c->last_pal_pic || !ctx->last_pic) {
-        mss2_decode_end(avctx);
-        return AVERROR(ENOMEM);
-    }
-    if (ret = wmv9_init(avctx)) {
-        mss2_decode_end(avctx);
-        return ret;
-    }
-    ff_mss2dsp_init(&ctx->dsp);
-
-    avctx->pix_fmt = c->free_colours == 127 ? AV_PIX_FMT_RGB555
-                                            : AV_PIX_FMT_RGB24;
-
-
-    return 0;
-}
-
-AVCodec ff_mss2_decoder = {
-    .name           = "mss2",
-    .long_name      = NULL_IF_CONFIG_SMALL("MS Windows Media Video V9 Screen"),
-    .type           = AVMEDIA_TYPE_VIDEO,
-    .id             = AV_CODEC_ID_MSS2,
-    .priv_data_size = sizeof(MSS2Context),
-    .init           = mss2_decode_init,
-    .close          = mss2_decode_end,
-    .decode         = mss2_decode_frame,
-    .capabilities   = CODEC_CAP_DR1,
-};