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Code Issues Releases Activity

mpeg12dec: Use more specific error codes

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Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>
This commit is contained in:
Michael Niedermayer
2014-11-24 17:05:00 +00:00
committed by Vittorio Giovara
parent b56afb48ae
commit 3a56bcee7c
1 changed files with 51 additions and 51 deletions
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102
libavcodec/mpeg12dec.c
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@@ -149,7 +149,7 @@ static inline int mpeg1_decode_block_intra(MpegEncContext *s,
component = (n <= 3 ? 0 : n - 4 + 1); component = (n <= 3 ? 0 : n - 4 + 1);
diff = decode_dc(&s->gb, component); diff = decode_dc(&s->gb, component);
if (diff >= 0xffff) if (diff >= 0xffff)
return -1; return AVERROR_INVALIDDATA;
dc = s->last_dc[component]; dc = s->last_dc[component];
dc += diff; dc += diff;
s->last_dc[component] = dc; s->last_dc[component] = dc;
@@ -545,7 +545,7 @@ static inline int mpeg2_decode_block_intra(MpegEncContext *s,
} }
diff = decode_dc(&s->gb, component); diff = decode_dc(&s->gb, component);
if (diff >= 0xffff) if (diff >= 0xffff)
return -1; return AVERROR_INVALIDDATA;
dc = s->last_dc[component]; dc = s->last_dc[component];
dc += diff; dc += diff;
s->last_dc[component] = dc; s->last_dc[component] = dc;
@@ -625,7 +625,7 @@ static inline int mpeg2_fast_decode_block_intra(MpegEncContext *s,
} }
diff = decode_dc(&s->gb, component); diff = decode_dc(&s->gb, component);
if (diff >= 0xffff) if (diff >= 0xffff)
return -1; return AVERROR_INVALIDDATA;
dc = s->last_dc[component]; dc = s->last_dc[component];
dc += diff; dc += diff;
s->last_dc[component] = dc; s->last_dc[component] = dc;
@@ -711,6 +711,7 @@ static int mpeg_decode_mb(MpegEncContext *s, int16_t block[12][64])
{ {
int i, j, k, cbp, val, mb_type, motion_type; int i, j, k, cbp, val, mb_type, motion_type;
const int mb_block_count = 4 + (1 << s->chroma_format); const int mb_block_count = 4 + (1 << s->chroma_format);
int ret;
av_dlog(s->avctx, "decode_mb: x=%d y=%d\n", s->mb_x, s->mb_y); av_dlog(s->avctx, "decode_mb: x=%d y=%d\n", s->mb_x, s->mb_y);
@@ -730,7 +731,7 @@ static int mpeg_decode_mb(MpegEncContext *s, int16_t block[12][64])
// FIXME not sure if this is allowed in MPEG at all // FIXME not sure if this is allowed in MPEG at all
mb_type = s->current_picture.mb_type[s->mb_width + (s->mb_y - 1) * s->mb_stride - 1]; mb_type = s->current_picture.mb_type[s->mb_width + (s->mb_y - 1) * s->mb_stride - 1];
if (IS_INTRA(mb_type)) if (IS_INTRA(mb_type))
return -1; return AVERROR_INVALIDDATA;
s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride] = s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride] =
mb_type | MB_TYPE_SKIP; mb_type | MB_TYPE_SKIP;
// assert(s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride - 1] & (MB_TYPE_16x16 | MB_TYPE_16x8)); // assert(s->current_picture.mb_type[s->mb_x + s->mb_y * s->mb_stride - 1] & (MB_TYPE_16x16 | MB_TYPE_16x8));
@@ -750,7 +751,7 @@ static int mpeg_decode_mb(MpegEncContext *s, int16_t block[12][64])
av_log(s->avctx, AV_LOG_ERROR, av_log(s->avctx, AV_LOG_ERROR,
"invalid mb type in I Frame at %d %d\n", "invalid mb type in I Frame at %d %d\n",
s->mb_x, s->mb_y); s->mb_x, s->mb_y);
return -1; return AVERROR_INVALIDDATA;
} }
mb_type = MB_TYPE_QUANT | MB_TYPE_INTRA; mb_type = MB_TYPE_QUANT | MB_TYPE_INTRA;
} else { } else {
@@ -762,7 +763,7 @@ static int mpeg_decode_mb(MpegEncContext *s, int16_t block[12][64])
if (mb_type < 0) { if (mb_type < 0) {
av_log(s->avctx, AV_LOG_ERROR, av_log(s->avctx, AV_LOG_ERROR,
"invalid mb type in P Frame at %d %d\n", s->mb_x, s->mb_y); "invalid mb type in P Frame at %d %d\n", s->mb_x, s->mb_y);
return -1; return AVERROR_INVALIDDATA;
} }
mb_type = ptype2mb_type[mb_type]; mb_type = ptype2mb_type[mb_type];
break; break;
@@ -771,7 +772,7 @@ static int mpeg_decode_mb(MpegEncContext *s, int16_t block[12][64])
if (mb_type < 0) { if (mb_type < 0) {
av_log(s->avctx, AV_LOG_ERROR, av_log(s->avctx, AV_LOG_ERROR,
"invalid mb type in B Frame at %d %d\n", s->mb_x, s->mb_y); "invalid mb type in B Frame at %d %d\n", s->mb_x, s->mb_y);
return -1; return AVERROR_INVALIDDATA;
} }
mb_type = btype2mb_type[mb_type]; mb_type = btype2mb_type[mb_type];
break; break;
@@ -827,13 +828,13 @@ FF_ENABLE_DEPRECATION_WARNINGS
mpeg2_fast_decode_block_intra(s, *s->pblocks[i], i); mpeg2_fast_decode_block_intra(s, *s->pblocks[i], i);
} else { } else {
for (i = 0; i < mb_block_count; i++) for (i = 0; i < mb_block_count; i++)
if (mpeg2_decode_block_intra(s, *s->pblocks[i], i) < 0) if ((ret = mpeg2_decode_block_intra(s, *s->pblocks[i], i)) < 0)
return -1; return ret;
} }
} else { } else {
for (i = 0; i < 6; i++) for (i = 0; i < 6; i++)
if (mpeg1_decode_block_intra(s, *s->pblocks[i], i) < 0) if ((ret = mpeg1_decode_block_intra(s, *s->pblocks[i], i)) < 0)
return -1; return ret;
} }
} else { } else {
if (mb_type & MB_TYPE_ZERO_MV) { if (mb_type & MB_TYPE_ZERO_MV) {
@@ -1011,7 +1012,7 @@ FF_ENABLE_DEPRECATION_WARNINGS
default: default:
av_log(s->avctx, AV_LOG_ERROR, av_log(s->avctx, AV_LOG_ERROR,
"00 motion_type at %d %d\n", s->mb_x, s->mb_y); "00 motion_type at %d %d\n", s->mb_x, s->mb_y);
return -1; return AVERROR_INVALIDDATA;
} }
} }
@@ -1028,7 +1029,7 @@ FF_ENABLE_DEPRECATION_WARNINGS
if (cbp <= 0) { if (cbp <= 0) {
av_log(s->avctx, AV_LOG_ERROR, av_log(s->avctx, AV_LOG_ERROR,
"invalid cbp at %d %d\n", s->mb_x, s->mb_y); "invalid cbp at %d %d\n", s->mb_x, s->mb_y);
return -1; return AVERROR_INVALIDDATA;
} }
#if FF_API_XVMC #if FF_API_XVMC
@@ -1053,8 +1054,8 @@ FF_ENABLE_DEPRECATION_WARNINGS
for (i = 0; i < mb_block_count; i++) { for (i = 0; i < mb_block_count; i++) {
if (cbp & (1 << 11)) { if (cbp & (1 << 11)) {
if (mpeg2_decode_block_non_intra(s, *s->pblocks[i], i) < 0) if ((ret = mpeg2_decode_block_non_intra(s, *s->pblocks[i], i)) < 0)
return -1; return ret;
} else { } else {
s->block_last_index[i] = -1; s->block_last_index[i] = -1;
} }
@@ -1073,8 +1074,8 @@ FF_ENABLE_DEPRECATION_WARNINGS
} else { } else {
for (i = 0; i < 6; i++) { for (i = 0; i < 6; i++) {
if (cbp & 32) { if (cbp & 32) {
if (mpeg1_decode_block_inter(s, *s->pblocks[i], i) < 0) if ((ret = mpeg1_decode_block_inter(s, *s->pblocks[i], i)) < 0)
return -1; return ret;
} else { } else {
s->block_last_index[i] = -1; s->block_last_index[i] = -1;
} }
@@ -1241,9 +1242,6 @@ static int mpeg_decode_postinit(AVCodecContext *avctx)
s->parse_context = pc; s->parse_context = pc;
} }
if ((s->width == 0) || (s->height == 0))
return -2;
ret = ff_set_dimensions(avctx, s->width, s->height); ret = ff_set_dimensions(avctx, s->width, s->height);
if (ret < 0) if (ret < 0)
return ret; return ret;
@@ -1327,8 +1325,8 @@ static int mpeg_decode_postinit(AVCodecContext *avctx)
memcpy(old_permutation, s->idsp.idct_permutation, 64 * sizeof(uint8_t)); memcpy(old_permutation, s->idsp.idct_permutation, 64 * sizeof(uint8_t));
ff_mpv_idct_init(s); ff_mpv_idct_init(s);
if (ff_mpv_common_init(s) < 0) if ((ret = ff_mpv_common_init(s)) < 0)
return -2; return ret;
quant_matrix_rebuild(s->intra_matrix, old_permutation, s->idsp.idct_permutation); quant_matrix_rebuild(s->intra_matrix, old_permutation, s->idsp.idct_permutation);
quant_matrix_rebuild(s->inter_matrix, old_permutation, s->idsp.idct_permutation); quant_matrix_rebuild(s->inter_matrix, old_permutation, s->idsp.idct_permutation);
@@ -1352,7 +1350,7 @@ static int mpeg1_decode_picture(AVCodecContext *avctx, const uint8_t *buf,
ref = get_bits(&s->gb, 10); /* temporal ref */ ref = get_bits(&s->gb, 10); /* temporal ref */
s->pict_type = get_bits(&s->gb, 3); s->pict_type = get_bits(&s->gb, 3);
if (s->pict_type == 0 || s->pict_type > 3) if (s->pict_type == 0 || s->pict_type > 3)
return -1; return AVERROR_INVALIDDATA;
vbv_delay = get_bits(&s->gb, 16); vbv_delay = get_bits(&s->gb, 16);
if (s->pict_type == AV_PICTURE_TYPE_P || if (s->pict_type == AV_PICTURE_TYPE_P ||
@@ -1360,7 +1358,7 @@ static int mpeg1_decode_picture(AVCodecContext *avctx, const uint8_t *buf,
s->full_pel[0] = get_bits1(&s->gb); s->full_pel[0] = get_bits1(&s->gb);
f_code = get_bits(&s->gb, 3); f_code = get_bits(&s->gb, 3);
if (f_code == 0 && (avctx->err_recognition & AV_EF_BITSTREAM)) if (f_code == 0 && (avctx->err_recognition & AV_EF_BITSTREAM))
return -1; return AVERROR_INVALIDDATA;
s->mpeg_f_code[0][0] = f_code; s->mpeg_f_code[0][0] = f_code;
s->mpeg_f_code[0][1] = f_code; s->mpeg_f_code[0][1] = f_code;
} }
@@ -1368,7 +1366,7 @@ static int mpeg1_decode_picture(AVCodecContext *avctx, const uint8_t *buf,
s->full_pel[1] = get_bits1(&s->gb); s->full_pel[1] = get_bits1(&s->gb);
f_code = get_bits(&s->gb, 3); f_code = get_bits(&s->gb, 3);
if (f_code == 0 && (avctx->err_recognition & AV_EF_BITSTREAM)) if (f_code == 0 && (avctx->err_recognition & AV_EF_BITSTREAM))
return -1; return AVERROR_INVALIDDATA;
s->mpeg_f_code[1][0] = f_code; s->mpeg_f_code[1][0] = f_code;
s->mpeg_f_code[1][1] = f_code; s->mpeg_f_code[1][1] = f_code;
} }
@@ -1489,7 +1487,7 @@ static int load_matrix(MpegEncContext *s, uint16_t matrix0[64],
int v = get_bits(&s->gb, 8); int v = get_bits(&s->gb, 8);
if (v == 0) { if (v == 0) {
av_log(s->avctx, AV_LOG_ERROR, "matrix damaged\n"); av_log(s->avctx, AV_LOG_ERROR, "matrix damaged\n");
return -1; return AVERROR_INVALIDDATA;
} }
if (intra && i == 0 && v != 8) { if (intra && i == 0 && v != 8) {
av_log(s->avctx, AV_LOG_ERROR, "intra matrix invalid, ignoring\n"); av_log(s->avctx, AV_LOG_ERROR, "intra matrix invalid, ignoring\n");
@@ -1600,13 +1598,14 @@ static int mpeg_field_start(MpegEncContext *s, const uint8_t *buf, int buf_size)
{ {
AVCodecContext *avctx = s->avctx; AVCodecContext *avctx = s->avctx;
Mpeg1Context *s1 = (Mpeg1Context *) s; Mpeg1Context *s1 = (Mpeg1Context *) s;
int ret;
/* start frame decoding */ /* start frame decoding */
if (s->first_field || s->picture_structure == PICT_FRAME) { if (s->first_field || s->picture_structure == PICT_FRAME) {
AVFrameSideData *pan_scan; AVFrameSideData *pan_scan;
if (ff_mpv_frame_start(s, avctx) < 0) if ((ret = ff_mpv_frame_start(s, avctx)) < 0)
return -1; return ret;
ff_mpeg_er_frame_start(s); ff_mpeg_er_frame_start(s);
@@ -1666,7 +1665,7 @@ static int mpeg_field_start(MpegEncContext *s, const uint8_t *buf, int buf_size)
if (!s->current_picture_ptr) { if (!s->current_picture_ptr) {
av_log(s->avctx, AV_LOG_ERROR, "first field missing\n"); av_log(s->avctx, AV_LOG_ERROR, "first field missing\n");
return -1; return AVERROR_INVALIDDATA;
} }
if (s->avctx->hwaccel && if (s->avctx->hwaccel &&
@@ -1685,8 +1684,8 @@ static int mpeg_field_start(MpegEncContext *s, const uint8_t *buf, int buf_size)
} }
if (avctx->hwaccel) { if (avctx->hwaccel) {
if (avctx->hwaccel->start_frame(avctx, buf, buf_size) < 0) if ((ret = avctx->hwaccel->start_frame(avctx, buf, buf_size)) < 0)
return -1; return ret;
} }
#if FF_API_XVMC #if FF_API_XVMC
@@ -1716,6 +1715,7 @@ static int mpeg_decode_slice(MpegEncContext *s, int mb_y,
{ {
AVCodecContext *avctx = s->avctx; AVCodecContext *avctx = s->avctx;
const int field_pic = s->picture_structure != PICT_FRAME; const int field_pic = s->picture_structure != PICT_FRAME;
int ret;
s->resync_mb_x = s->resync_mb_x =
s->resync_mb_y = -1; s->resync_mb_y = -1;
@@ -1731,7 +1731,7 @@ static int mpeg_decode_slice(MpegEncContext *s, int mb_y,
if (s->qscale == 0) { if (s->qscale == 0) {
av_log(s->avctx, AV_LOG_ERROR, "qscale == 0\n"); av_log(s->avctx, AV_LOG_ERROR, "qscale == 0\n");
return -1; return AVERROR_INVALIDDATA;
} }
/* extra slice info */ /* extra slice info */
@@ -1748,7 +1748,7 @@ static int mpeg_decode_slice(MpegEncContext *s, int mb_y,
MBINCR_VLC_BITS, 2); MBINCR_VLC_BITS, 2);
if (code < 0) { if (code < 0) {
av_log(s->avctx, AV_LOG_ERROR, "first mb_incr damaged\n"); av_log(s->avctx, AV_LOG_ERROR, "first mb_incr damaged\n");
return -1; return AVERROR_INVALIDDATA;
} }
if (code >= 33) { if (code >= 33) {
if (code == 33) if (code == 33)
@@ -1763,7 +1763,7 @@ static int mpeg_decode_slice(MpegEncContext *s, int mb_y,
if (s->mb_x >= (unsigned) s->mb_width) { if (s->mb_x >= (unsigned) s->mb_width) {
av_log(s->avctx, AV_LOG_ERROR, "initial skip overflow\n"); av_log(s->avctx, AV_LOG_ERROR, "initial skip overflow\n");
return -1; return AVERROR_INVALIDDATA;
} }
if (avctx->hwaccel) { if (avctx->hwaccel) {
@@ -1814,8 +1814,8 @@ FF_DISABLE_DEPRECATION_WARNINGS
FF_ENABLE_DEPRECATION_WARNINGS FF_ENABLE_DEPRECATION_WARNINGS
#endif /* FF_API_XVMC */ #endif /* FF_API_XVMC */
if (mpeg_decode_mb(s, s->block) < 0) if ((ret = mpeg_decode_mb(s, s->block)) < 0)
return -1; return ret;
// Note motion_val is normally NULL unless we want to extract the MVs. // Note motion_val is normally NULL unless we want to extract the MVs.
if (s->current_picture.motion_val[0] && !s->encoding) { if (s->current_picture.motion_val[0] && !s->encoding) {
@@ -1882,7 +1882,7 @@ FF_ENABLE_DEPRECATION_WARNINGS
((avctx->err_recognition & AV_EF_BUFFER) && left > 8)) { ((avctx->err_recognition & AV_EF_BUFFER) && left > 8)) {
av_log(avctx, AV_LOG_ERROR, "end mismatch left=%d %0X\n", av_log(avctx, AV_LOG_ERROR, "end mismatch left=%d %0X\n",
left, show_bits(&s->gb, FFMIN(left, 23))); left, show_bits(&s->gb, FFMIN(left, 23)));
return -1; return AVERROR_INVALIDDATA;
} else } else
goto eos; goto eos;
} }
@@ -1899,7 +1899,7 @@ FF_ENABLE_DEPRECATION_WARNINGS
MBINCR_VLC_BITS, 2); MBINCR_VLC_BITS, 2);
if (code < 0) { if (code < 0) {
av_log(s->avctx, AV_LOG_ERROR, "mb incr damaged\n"); av_log(s->avctx, AV_LOG_ERROR, "mb incr damaged\n");
return -1; return AVERROR_INVALIDDATA;
} }
if (code >= 33) { if (code >= 33) {
if (code == 33) { if (code == 33) {
@@ -1907,7 +1907,7 @@ FF_ENABLE_DEPRECATION_WARNINGS
} else if (code == 35) { } else if (code == 35) {
if (s->mb_skip_run != 0 || show_bits(&s->gb, 15) != 0) { if (s->mb_skip_run != 0 || show_bits(&s->gb, 15) != 0) {
av_log(s->avctx, AV_LOG_ERROR, "slice mismatch\n"); av_log(s->avctx, AV_LOG_ERROR, "slice mismatch\n");
return -1; return AVERROR_INVALIDDATA;
} }
goto eos; /* end of slice */ goto eos; /* end of slice */
} }
@@ -1922,7 +1922,7 @@ FF_ENABLE_DEPRECATION_WARNINGS
if (s->pict_type == AV_PICTURE_TYPE_I) { if (s->pict_type == AV_PICTURE_TYPE_I) {
av_log(s->avctx, AV_LOG_ERROR, av_log(s->avctx, AV_LOG_ERROR,
"skipped MB in I frame at %d %d\n", s->mb_x, s->mb_y); "skipped MB in I frame at %d %d\n", s->mb_x, s->mb_y);
return -1; return AVERROR_INVALIDDATA;
} }
/* skip mb */ /* skip mb */
@@ -1996,7 +1996,7 @@ static int slice_decode_thread(AVCodecContext *c, void *arg)
if (s->picture_structure == PICT_BOTTOM_FIELD) if (s->picture_structure == PICT_BOTTOM_FIELD)
mb_y++; mb_y++;
if (mb_y < 0 || mb_y >= s->end_mb_y) if (mb_y < 0 || mb_y >= s->end_mb_y)
return -1; return AVERROR_INVALIDDATA;
} }
} }
@@ -2079,18 +2079,18 @@ static int mpeg1_decode_sequence(AVCodecContext *avctx,
if (s->aspect_ratio_info == 0) { if (s->aspect_ratio_info == 0) {
av_log(avctx, AV_LOG_ERROR, "aspect ratio has forbidden 0 value\n"); av_log(avctx, AV_LOG_ERROR, "aspect ratio has forbidden 0 value\n");
if (avctx->err_recognition & AV_EF_BITSTREAM) if (avctx->err_recognition & AV_EF_BITSTREAM)
return -1; return AVERROR_INVALIDDATA;
} }
s->frame_rate_index = get_bits(&s->gb, 4); s->frame_rate_index = get_bits(&s->gb, 4);
if (s->frame_rate_index == 0 || s->frame_rate_index > 13) { if (s->frame_rate_index == 0 || s->frame_rate_index > 13) {
av_log(avctx, AV_LOG_WARNING, av_log(avctx, AV_LOG_WARNING,
"frame_rate_index %d is invalid\n", s->frame_rate_index); "frame_rate_index %d is invalid\n", s->frame_rate_index);
return -1; return AVERROR_INVALIDDATA;
} }
s->bit_rate = get_bits(&s->gb, 18) * 400; s->bit_rate = get_bits(&s->gb, 18) * 400;
if (get_bits1(&s->gb) == 0) { /* marker */ if (get_bits1(&s->gb) == 0) { /* marker */
av_log(avctx, AV_LOG_ERROR, "Marker in sequence header missing\n"); av_log(avctx, AV_LOG_ERROR, "Marker in sequence header missing\n");
return -1; return AVERROR_INVALIDDATA;
} }
s->width = width; s->width = width;
s->height = height; s->height = height;
@@ -2122,7 +2122,7 @@ static int mpeg1_decode_sequence(AVCodecContext *avctx,
if (show_bits(&s->gb, 23) != 0) { if (show_bits(&s->gb, 23) != 0) {
av_log(s->avctx, AV_LOG_ERROR, "sequence header damaged\n"); av_log(s->avctx, AV_LOG_ERROR, "sequence header damaged\n");
return -1; return AVERROR_INVALIDDATA;
} }
/* We set MPEG-2 parameters so that it emulates MPEG-1. */ /* We set MPEG-2 parameters so that it emulates MPEG-1. */
@@ -2148,7 +2148,7 @@ static int vcr2_init_sequence(AVCodecContext *avctx)
{ {
Mpeg1Context *s1 = avctx->priv_data; Mpeg1Context *s1 = avctx->priv_data;
MpegEncContext *s = &s1->mpeg_enc_ctx; MpegEncContext *s = &s1->mpeg_enc_ctx;
int i, v; int i, v, ret;
/* start new MPEG-1 context decoding */ /* start new MPEG-1 context decoding */
s->out_format = FMT_MPEG1; s->out_format = FMT_MPEG1;
@@ -2171,8 +2171,8 @@ static int vcr2_init_sequence(AVCodecContext *avctx)
avctx->idct_algo = FF_IDCT_SIMPLE; avctx->idct_algo = FF_IDCT_SIMPLE;
ff_mpv_idct_init(s); ff_mpv_idct_init(s);
if (ff_mpv_common_init(s) < 0) if ((ret = ff_mpv_common_init(s)) < 0)
return -1; return ret;
s1->mpeg_enc_ctx_allocated = 1; s1->mpeg_enc_ctx_allocated = 1;
for (i = 0; i < 64; i++) { for (i = 0; i < 64; i++) {
@@ -2505,7 +2505,7 @@ static int decode_chunks(AVCodecContext *avctx, AVFrame *picture,
if (mb_y >= s2->mb_height) { if (mb_y >= s2->mb_height) {
av_log(s2->avctx, AV_LOG_ERROR, av_log(s2->avctx, AV_LOG_ERROR,
"slice below image (%d >= %d)\n", mb_y, s2->mb_height); "slice below image (%d >= %d)\n", mb_y, s2->mb_height);
return -1; return AVERROR_INVALIDDATA;
} }
if (!s2->last_picture_ptr) { if (!s2->last_picture_ptr) {
@@ -2556,8 +2556,8 @@ static int decode_chunks(AVCodecContext *avctx, AVFrame *picture,
if (s->first_slice) { if (s->first_slice) {
skip_frame = 0; skip_frame = 0;
s->first_slice = 0; s->first_slice = 0;
if (mpeg_field_start(s2, buf, buf_size) < 0) if ((ret = mpeg_field_start(s2, buf, buf_size)) < 0)
return -1; return ret;
} }
if (!s2->current_picture_ptr) { if (!s2->current_picture_ptr) {
av_log(avctx, AV_LOG_ERROR, av_log(avctx, AV_LOG_ERROR,