Merge remote-tracking branch 'qatar/master'

* qatar/master:
  matroska: Clear prev_pkt between seeks.
  avutil: change default buffer size alignment for sample buffer functions
  audemux: Add a sanity check for the number of channels
  Remove libdirac decoder.
  matroska: Add incremental parsing of clusters.
  avconv: fix off by one check in complex_filter
  mpegts: Try seeking back even for nonseekable protocols
  swscale: K&R formatting cosmetics (part III)

Conflicts:
	configure
	doc/general.texi
	doc/platform.texi
	ffmpeg.c
	libavcodec/Makefile
	libavcodec/allcodecs.c
	libavcodec/libdirac.h
	libavcodec/libdiracdec.c
	libavformat/au.c
	libavformat/mpegts.c
	libswscale/input.c
	tests/ref/seek/lavf_mkv

Merged-by: Michael Niedermayer <michaelni@gmx.at>

configure

@@ -179,7 +179,6 @@ External library support:
   --enable-libcdio         enable audio CD grabbing with libcdio
   --enable-libdc1394       enable IIDC-1394 grabbing using libdc1394
                            and libraw1394 [no]
-  --enable-libdirac        enable Dirac support via libdirac [no]
   --enable-libfaac         enable FAAC support via libfaac [no]
   --enable-libfreetype     enable libfreetype [no]
   --enable-libgsm          enable GSM support via libgsm [no]
@@ -1035,7 +1034,6 @@ CONFIG_LIST="
     libcdio
     libcelt
     libdc1394
-    libdirac
     libfaac
     libfreetype
     libgsm
@@ -1557,7 +1555,6 @@ h264_parser_select="golomb h264dsp h264pred"
 # external libraries
 libaacplus_encoder_deps="libaacplus"
 libcelt_decoder_deps="libcelt"
-libdirac_decoder_deps="libdirac !libschroedinger"
 libfaac_encoder_deps="libfaac"
 libgsm_decoder_deps="libgsm"
 libgsm_encoder_deps="libgsm"
@@ -3200,9 +3197,6 @@ enabled libbluray  && require libbluray libbluray/bluray.h bd_open -lbluray
 enabled libcelt    && require libcelt celt/celt.h celt_decode -lcelt0 &&
                       { check_lib celt/celt.h celt_decoder_create_custom -lcelt0 ||
                         die "ERROR: libcelt version must be >= 0.11.0."; }
-enabled libdirac   && require_pkg_config dirac                          \
-    "libdirac_decoder/dirac_parser.h"  \
-    "dirac_decoder_init"
 enabled libfaac    && require2 libfaac "stdint.h faac.h" faacEncGetVersion -lfaac
 enabled libfreetype && require_pkg_config freetype2 "ft2build.h freetype/freetype.h" FT_Init_FreeType
 enabled libgsm     && require  libgsm gsm/gsm.h gsm_create -lgsm
@@ -3572,7 +3566,6 @@ echo "libass enabled            ${libass-no}"
 echo "libcdio support           ${libcdio-no}"
 echo "libcelt enabled           ${libcelt-no}"
 echo "libdc1394 support         ${libdc1394-no}"
-echo "libdirac enabled          ${libdirac-no}"
 echo "libfaac enabled           ${libfaac-no}"
 echo "libgsm enabled            ${libgsm-no}"
 echo "libmodplug enabled        ${libmodplug-no}"

doc/general.texi

@@ -482,7 +482,7 @@ following image formats are supported:
 @item DFA                    @tab     @tab  X
     @tab Codec used in Chronomaster game.
 @item Dirac                  @tab  E  @tab  X
-    @tab supported through external libdirac/libschroedinger libraries
+    @tab supported through external library libschroedinger
 @item Deluxe Paint Animation @tab     @tab  X
 @item DNxHD                  @tab   X @tab  X
     @tab aka SMPTE VC3

doc/platform.texi

@@ -354,9 +354,8 @@ These library packages are only available from
 @uref{http://sourceware.org/cygwinports/, Cygwin Ports}:
 
 @example
-yasm, libSDL-devel, libdirac-devel, libfaac-devel, libaacplus-devel, libgsm-devel,
-libmp3lame-devel, libschroedinger1.0-devel, speex-devel, libtheora-devel,
-libxvidcore-devel
+yasm, libSDL-devel, libfaac-devel, libaacplus-devel, libgsm-devel, libmp3lame-devel,
+libschroedinger1.0-devel, speex-devel, libtheora-devel, libxvidcore-devel
 @end example
 
 The recommendation for libnut and x264 is to build them from source by

libavcodec/Makefile

@@ -634,7 +634,6 @@ OBJS-$(CONFIG_WTV_DEMUXER)             += mpeg4audio.o mpegaudiodata.o
 # external codec libraries
 OBJS-$(CONFIG_LIBAACPLUS_ENCODER)         += libaacplus.o
 OBJS-$(CONFIG_LIBCELT_DECODER)            += libcelt_dec.o
-OBJS-$(CONFIG_LIBDIRAC_DECODER)           += libdiracdec.o
 OBJS-$(CONFIG_LIBFAAC_ENCODER)            += libfaac.o audio_frame_queue.o
 OBJS-$(CONFIG_LIBGSM_DECODER)             += libgsm.o
 OBJS-$(CONFIG_LIBGSM_ENCODER)             += libgsm.o
@@ -753,7 +752,6 @@ SKIPHEADERS                            += %_tablegen.h                  \
                                           tableprint.h                  \
                                           $(ARCH)/vp56_arith.h
 SKIPHEADERS-$(CONFIG_DXVA2)            += dxva2.h dxva2_internal.h
-SKIPHEADERS-$(CONFIG_LIBDIRAC)         += libdirac.h
 SKIPHEADERS-$(CONFIG_LIBSCHROEDINGER)  += libschroedinger.h
 SKIPHEADERS-$(CONFIG_MPEG_XVMC_DECODER) += xvmc.h
 SKIPHEADERS-$(CONFIG_VAAPI)            += vaapi_internal.h

libavcodec/allcodecs.c

@@ -403,7 +403,6 @@ void avcodec_register_all(void)
 
     /* external libraries */
     REGISTER_DECODER (LIBCELT, libcelt);
-    REGISTER_DECODER (LIBDIRAC, libdirac);
     REGISTER_ENCODER (LIBFAAC, libfaac);
     REGISTER_ENCDEC  (LIBGSM, libgsm);
     REGISTER_ENCDEC  (LIBGSM_MS, libgsm_ms);

libavcodec/libdirac.h

@@ -1,44 +0,0 @@
-/*
- * Copyright (c) 2008 BBC, Anuradha Suraparaju <asuraparaju at gmail dot com >
- *
- * 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
-* data structures common to libdirac encoder and decoder
-*/
-
-#ifndef AVCODEC_LIBDIRAC_H
-#define AVCODEC_LIBDIRAC_H
-
-#include "avcodec.h"
-#include <libdirac_common/dirac_types.h>
-
-/**
-* Table providing a Dirac chroma format to FFmpeg pixel format mapping.
-*/
-static const struct {
-    enum PixelFormat ff_pix_fmt;
-    dirac_chroma_t dirac_pix_fmt;
-} dirac_pixel_format_map[] = {
-    { PIX_FMT_YUV420P, format420 },
-    { PIX_FMT_YUV422P, format422 },
-    { PIX_FMT_YUV444P, format444 },
-};
-
-#endif /* AVCODEC_LIBDIRAC_H */

libavcodec/libdiracdec.c

@@ -1,208 +0,0 @@
-/*
- * Dirac decoder support via libdirac library
- * Copyright (c) 2005 BBC, Andrew Kennedy <dirac at rd dot bbc dot co dot uk>
- * Copyright (c) 2006-2008 BBC, Anuradha Suraparaju <asuraparaju at gmail dot com >
- *
- * 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
-* Dirac decoder support via libdirac library; more details about the Dirac
-* project can be found at http://dirac.sourceforge.net/.
-* The libdirac_decoder library implements Dirac specification version 2.2
-* (http://dirac.sourceforge.net/specification.html).
-*/
-
-#include "libavutil/imgutils.h"
-#include "libdirac.h"
-
-#undef NDEBUG
-#include <assert.h>
-
-#include <libdirac_decoder/dirac_parser.h>
-
-/** contains a single frame returned from Dirac */
-typedef struct DiracDecoderParams {
-    /** decoder handle */
-    dirac_decoder_t* p_decoder;
-
-    /** buffer to hold decoded frame */
-    unsigned char* p_out_frame_buf;
-} DiracDecoderParams;
-
-
-/**
-* returns FFmpeg chroma format
-*/
-static enum PixelFormat get_chroma_format(dirac_chroma_t dirac_pix_fmt)
-{
-    int num_formats = sizeof(dirac_pixel_format_map) /
-                      sizeof(dirac_pixel_format_map[0]);
-    int idx;
-
-    for (idx = 0; idx < num_formats; ++idx)
-        if (dirac_pixel_format_map[idx].dirac_pix_fmt == dirac_pix_fmt)
-            return dirac_pixel_format_map[idx].ff_pix_fmt;
-    return PIX_FMT_NONE;
-}
-
-static av_cold int libdirac_decode_init(AVCodecContext *avccontext)
-{
-
-    DiracDecoderParams *p_dirac_params = avccontext->priv_data;
-    p_dirac_params->p_decoder =  dirac_decoder_init(avccontext->debug);
-
-    if (!p_dirac_params->p_decoder)
-        return -1;
-
-    return 0;
-}
-
-static int libdirac_decode_frame(AVCodecContext *avccontext,
-                                 void *data, int *data_size,
-                                 AVPacket *avpkt)
-{
-    const uint8_t *buf = avpkt->data;
-    int buf_size = avpkt->size;
-
-    DiracDecoderParams *p_dirac_params = avccontext->priv_data;
-    AVPicture *picture = data;
-    AVPicture pic;
-    int pict_size;
-    unsigned char *buffer[3];
-
-    *data_size = 0;
-
-    if (buf_size > 0) {
-        /* set data to decode into buffer */
-        dirac_buffer(p_dirac_params->p_decoder, buf, buf + buf_size);
-        if ((buf[4] & 0x08) == 0x08 && (buf[4] & 0x03))
-            avccontext->has_b_frames = 1;
-    }
-    while (1) {
-         /* parse data and process result */
-        DecoderState state = dirac_parse(p_dirac_params->p_decoder);
-        switch (state) {
-        case STATE_BUFFER:
-            return buf_size;
-
-        case STATE_SEQUENCE:
-        {
-            /* tell FFmpeg about sequence details */
-            dirac_sourceparams_t *src_params = &p_dirac_params->p_decoder->src_params;
-
-            if (av_image_check_size(src_params->width, src_params->height,
-                                    0, avccontext) < 0) {
-                av_log(avccontext, AV_LOG_ERROR, "Invalid dimensions (%dx%d)\n",
-                       src_params->width, src_params->height);
-                avccontext->height = avccontext->width = 0;
-                return -1;
-            }
-
-            avccontext->height = src_params->height;
-            avccontext->width  = src_params->width;
-
-            avccontext->pix_fmt = get_chroma_format(src_params->chroma);
-            if (avccontext->pix_fmt == PIX_FMT_NONE) {
-                av_log(avccontext, AV_LOG_ERROR,
-                       "Dirac chroma format %d not supported currently\n",
-                       src_params->chroma);
-                return -1;
-            }
-
-            avccontext->time_base.den = src_params->frame_rate.numerator;
-            avccontext->time_base.num = src_params->frame_rate.denominator;
-
-            /* calculate output dimensions */
-            avpicture_fill(&pic, NULL, avccontext->pix_fmt,
-                           avccontext->width, avccontext->height);
-
-            pict_size = avpicture_get_size(avccontext->pix_fmt,
-                                           avccontext->width,
-                                           avccontext->height);
-
-            /* allocate output buffer */
-            if (!p_dirac_params->p_out_frame_buf)
-                p_dirac_params->p_out_frame_buf = av_malloc(pict_size);
-            buffer[0] = p_dirac_params->p_out_frame_buf;
-            buffer[1] = p_dirac_params->p_out_frame_buf +
-                        pic.linesize[0] * avccontext->height;
-            buffer[2] = buffer[1] +
-                        pic.linesize[1] * src_params->chroma_height;
-
-            /* tell Dirac about output destination */
-            dirac_set_buf(p_dirac_params->p_decoder, buffer, NULL);
-            break;
-        }
-        case STATE_SEQUENCE_END:
-            break;
-
-        case STATE_PICTURE_AVAIL:
-            /* fill picture with current buffer data from Dirac */
-            avpicture_fill(picture, p_dirac_params->p_out_frame_buf,
-                           avccontext->pix_fmt,
-                           avccontext->width, avccontext->height);
-            *data_size = sizeof(AVPicture);
-            return buf_size;
-
-        case STATE_INVALID:
-            return -1;
-
-        default:
-            break;
-        }
-    }
-
-    return buf_size;
-}
-
-
-static av_cold int libdirac_decode_close(AVCodecContext *avccontext)
-{
-    DiracDecoderParams *p_dirac_params = avccontext->priv_data;
-    dirac_decoder_close(p_dirac_params->p_decoder);
-
-    av_freep(&p_dirac_params->p_out_frame_buf);
-
-    return 0;
-}
-
-static void libdirac_flush(AVCodecContext *avccontext)
-{
-    /* Got a seek request. We will need free memory held in the private
-     * context and free the current Dirac decoder handle and then open
-     * a new decoder handle. */
-    libdirac_decode_close(avccontext);
-    libdirac_decode_init(avccontext);
-    return;
-}
-
-
-
-AVCodec ff_libdirac_decoder = {
-    .name           = "libdirac",
-    .type           = AVMEDIA_TYPE_VIDEO,
-    .id             = CODEC_ID_DIRAC,
-    .priv_data_size = sizeof(DiracDecoderParams),
-    .init           = libdirac_decode_init,
-    .close          = libdirac_decode_close,
-    .decode         = libdirac_decode_frame,
-    .capabilities   = CODEC_CAP_DELAY,
-    .flush          = libdirac_flush,
-    .long_name      = NULL_IF_CONFIG_SMALL("libdirac Dirac 2.2"),
-};

libavformat/au.c

@@ -150,7 +150,7 @@ static int au_read_header(AVFormatContext *s)
         return AVERROR_INVALIDDATA;
     }
 
-    if (channels <= 0) {
+    if (channels == 0 || channels > 64) {
         av_log(s, AV_LOG_ERROR, "Invalid number of channels %d\n", channels);
         return AVERROR_INVALIDDATA;
     }

libavformat/matroskadec.c

@@ -223,6 +223,11 @@ typedef struct {
     uint64_t length;
 } MatroskaLevel;
 
+typedef struct {
+    uint64_t timecode;
+    EbmlList blocks;
+} MatroskaCluster;
+
 typedef struct {
     AVFormatContext *ctx;
 
@@ -259,6 +264,13 @@ typedef struct {
 
     /* File has a CUES element, but we defer parsing until it is needed. */
     int cues_parsing_deferred;
+
+    int current_cluster_num_blocks;
+    int64_t current_cluster_pos;
+    MatroskaCluster current_cluster;
+
+    /* File has SSA subtitles which prevent incremental cluster parsing. */
+    int contains_ssa;
 } MatroskaDemuxContext;
 
 typedef struct {
@@ -268,11 +280,6 @@ typedef struct {
     EbmlBin  bin;
 } MatroskaBlock;
 
-typedef struct {
-    uint64_t timecode;
-    EbmlList blocks;
-} MatroskaCluster;
-
 static EbmlSyntax ebml_header[] = {
     { EBML_ID_EBMLREADVERSION,        EBML_UINT, 0, offsetof(Ebml,version), {.u=EBML_VERSION} },
     { EBML_ID_EBMLMAXSIZELENGTH,      EBML_UINT, 0, offsetof(Ebml,max_size), {.u=8} },
@@ -543,6 +550,38 @@ static EbmlSyntax matroska_clusters[] = {
     { 0 }
 };
 
+static EbmlSyntax matroska_cluster_incremental_parsing[] = {
+    { MATROSKA_ID_CLUSTERTIMECODE,EBML_UINT,0, offsetof(MatroskaCluster,timecode) },
+    { MATROSKA_ID_BLOCKGROUP,     EBML_NEST, sizeof(MatroskaBlock), offsetof(MatroskaCluster,blocks), {.n=matroska_blockgroup} },
+    { MATROSKA_ID_SIMPLEBLOCK,    EBML_PASS, sizeof(MatroskaBlock), offsetof(MatroskaCluster,blocks), {.n=matroska_blockgroup} },
+    { MATROSKA_ID_CLUSTERPOSITION,EBML_NONE },
+    { MATROSKA_ID_CLUSTERPREVSIZE,EBML_NONE },
+    { MATROSKA_ID_INFO,           EBML_NONE },
+    { MATROSKA_ID_CUES,           EBML_NONE },
+    { MATROSKA_ID_TAGS,           EBML_NONE },
+    { MATROSKA_ID_SEEKHEAD,       EBML_NONE },
+    { MATROSKA_ID_CLUSTER,        EBML_STOP },
+    { 0 }
+};
+
+static EbmlSyntax matroska_cluster_incremental[] = {
+    { MATROSKA_ID_CLUSTERTIMECODE,EBML_UINT,0, offsetof(MatroskaCluster,timecode) },
+    { MATROSKA_ID_BLOCKGROUP,     EBML_STOP },
+    { MATROSKA_ID_SIMPLEBLOCK,    EBML_STOP },
+    { MATROSKA_ID_CLUSTERPOSITION,EBML_NONE },
+    { MATROSKA_ID_CLUSTERPREVSIZE,EBML_NONE },
+    { 0 }
+};
+
+static EbmlSyntax matroska_clusters_incremental[] = {
+    { MATROSKA_ID_CLUSTER,        EBML_NEST, 0, 0, {.n=matroska_cluster_incremental} },
+    { MATROSKA_ID_INFO,           EBML_NONE },
+    { MATROSKA_ID_CUES,           EBML_NONE },
+    { MATROSKA_ID_TAGS,           EBML_NONE },
+    { MATROSKA_ID_SEEKHEAD,       EBML_NONE },
+    { 0 }
+};
+
 static const char *const matroska_doctypes[] = { "matroska", "webm" };
 
 static int matroska_resync(MatroskaDemuxContext *matroska, int64_t last_pos)
@@ -1693,6 +1732,8 @@ static int matroska_read_header(AVFormatContext *s)
             st->need_parsing = AVSTREAM_PARSE_HEADERS;
         } else if (track->type == MATROSKA_TRACK_TYPE_SUBTITLE) {
             st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE;
+            if (st->codec->codec_id == CODEC_ID_SSA)
+                matroska->contains_ssa = 1;
         }
     }
 
@@ -1766,6 +1807,7 @@ static int matroska_deliver_packet(MatroskaDemuxContext *matroska,
                 matroska->packets = newpackets;
         } else {
             av_freep(&matroska->packets);
+            matroska->prev_pkt = NULL;
         }
         matroska->num_packets--;
         return 0;
@@ -1822,6 +1864,7 @@ static int matroska_parse_block(MatroskaDemuxContext *matroska, uint8_t *data,
     st = track->stream;
     if (st->discard >= AVDISCARD_ALL)
         return res;
+    av_assert1(duration != AV_NOPTS_VALUE);
     if (!duration)
         duration = track->default_duration / matroska->time_scale;
 
@@ -2066,13 +2109,71 @@ end:
     return res;
 }
 
+static int matroska_parse_cluster_incremental(MatroskaDemuxContext *matroska)
+{
+    EbmlList *blocks_list;
+    MatroskaBlock *blocks;
+    int i, res;
+    res = ebml_parse(matroska,
+                     matroska_cluster_incremental_parsing,
+                     &matroska->current_cluster);
+    if (res == 1) {
+        /* New Cluster */
+        if (matroska->current_cluster_pos)
+            ebml_level_end(matroska);
+        ebml_free(matroska_cluster, &matroska->current_cluster);
+        memset(&matroska->current_cluster, 0, sizeof(MatroskaCluster));
+        matroska->current_cluster_num_blocks = 0;
+        matroska->current_cluster_pos = avio_tell(matroska->ctx->pb);
+        matroska->prev_pkt = NULL;
+        /* sizeof the ID which was already read */
+        if (matroska->current_id)
+            matroska->current_cluster_pos -= 4;
+        res = ebml_parse(matroska,
+                         matroska_clusters_incremental,
+                         &matroska->current_cluster);
+        /* Try parsing the block again. */
+        if (res == 1)
+            res = ebml_parse(matroska,
+                             matroska_cluster_incremental_parsing,
+                             &matroska->current_cluster);
+    }
+
+    if (!res &&
+        matroska->current_cluster_num_blocks <
+            matroska->current_cluster.blocks.nb_elem) {
+        blocks_list = &matroska->current_cluster.blocks;
+        blocks = blocks_list->elem;
+
+        matroska->current_cluster_num_blocks = blocks_list->nb_elem;
+        i = blocks_list->nb_elem - 1;
+        if (blocks[i].bin.size > 0 && blocks[i].bin.data) {
+            int is_keyframe = blocks[i].non_simple ? !blocks[i].reference : -1;
+            if (!blocks[i].non_simple)
+                blocks[i].duration = 0;
+            res = matroska_parse_block(matroska,
+                                       blocks[i].bin.data, blocks[i].bin.size,
+                                       blocks[i].bin.pos,
+                                       matroska->current_cluster.timecode,
+                                       blocks[i].duration, is_keyframe,
+                                       matroska->current_cluster_pos);
+        }
+    }
+
+    if (res < 0)  matroska->done = 1;
+    return res;
+}
+
 static int matroska_parse_cluster(MatroskaDemuxContext *matroska)
 {
     MatroskaCluster cluster = { 0 };
     EbmlList *blocks_list;
     MatroskaBlock *blocks;
     int i, res;
-    int64_t pos = avio_tell(matroska->ctx->pb);
+    int64_t pos;
+    if (!matroska->contains_ssa)
+        return matroska_parse_cluster_incremental(matroska);
+    pos = avio_tell(matroska->ctx->pb);
     matroska->prev_pkt = NULL;
     if (matroska->current_id)
         pos -= 4;  /* sizeof the ID which was already read */
@@ -2129,6 +2230,7 @@ static int matroska_read_seek(AVFormatContext *s, int stream_index,
         avio_seek(s->pb, st->index_entries[st->nb_index_entries-1].pos, SEEK_SET);
         matroska->current_id = 0;
         while ((index = av_index_search_timestamp(st, timestamp, flags)) < 0) {
+            matroska->prev_pkt = NULL;
             matroska_clear_queue(matroska);
             if (matroska_parse_cluster(matroska) < 0)
                 break;
@@ -2187,6 +2289,7 @@ static int matroska_read_close(AVFormatContext *s)
     for (n=0; n < matroska->tracks.nb_elem; n++)
         if (tracks[n].type == MATROSKA_TRACK_TYPE_AUDIO)
             av_free(tracks[n].audio.buf);
+    ebml_free(matroska_cluster, &matroska->current_cluster);
     ebml_free(matroska_segment, matroska);
 
     return 0;

libavutil/samplefmt.c

@@ -133,8 +133,10 @@ int av_samples_get_buffer_size(int *linesize, int nb_channels, int nb_samples,
         return AVERROR(EINVAL);
 
     /* auto-select alignment if not specified */
-    if (!align)
-        align = 32;
+    if (!align) {
+        align = 1;
+        nb_samples = FFALIGN(nb_samples, 32);
+    }
 
     /* check for integer overflow */
     if (nb_channels > INT_MAX / align ||

tests/ref/seek/lavf_mkv

@@ -30,7 +30,7 @@ ret: 0         st: 0 flags:1  ts: 2.413000
 ret: 0         st: 0 flags:1 dts: 0.960000 pts: 0.960000 pos: 292193 size: 27834
 ret:-1         st: 1 flags:0  ts: 1.307000
 ret: 0         st: 1 flags:1  ts: 0.201000
-ret: 0         st: 1 flags:1 dts: 0.198000 pts: 0.198000 pos:    555 size:   208
+ret: 0         st: 1 flags:1 dts: 0.015000 pts: 0.015000 pos:    555 size:   208
 ret: 0         st:-1 flags:0  ts:-0.904994
 ret: 0         st: 1 flags:1 dts: 0.000000 pts: 0.000000 pos:    555 size:   208
 ret: 0         st:-1 flags:1  ts: 1.989173