[FFmpeg-cvslog] wavpack demuxer: export full wavpack blocks.

Anton Khirnov git at videolan.org
Tue May 28 11:57:18 CEST 2013


ffmpeg | branch: master | Anton Khirnov <anton at khirnov.net> | Sun May 26 21:09:22 2013 +0200| [5074f4545c439420daebe4c2f28ed216440b6ec7] | committer: Anton Khirnov

wavpack demuxer: export full wavpack blocks.

Currently the demuxer shaves the blocks and exports only the
information that is useful to the decoder.

Exporting the blocks just as they are stored is simpler to understand
and will make remuxing wavpack easier.

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=5074f4545c439420daebe4c2f28ed216440b6ec7
---

 libavcodec/wavpack.c |   33 +++++++--------
 libavformat/wv.c     |  114 +++++++++++++++++++-------------------------------
 2 files changed, 56 insertions(+), 91 deletions(-)

diff --git a/libavcodec/wavpack.c b/libavcodec/wavpack.c
index 1b2e62e..3a0fe27 100644
--- a/libavcodec/wavpack.c
+++ b/libavcodec/wavpack.c
@@ -33,6 +33,8 @@
  * WavPack lossless audio decoder
  */
 
+#define WV_HEADER_SIZE    32
+
 #define WV_MONO           0x00000004
 #define WV_JOINT_STEREO   0x00000010
 #define WV_FALSE_STEREO   0x40000000
@@ -1145,7 +1147,7 @@ static int wavpack_decode_frame(AVCodecContext *avctx, void *data,
     AVFrame *frame     = data;
     int frame_size, ret, frame_flags;
 
-    if (avpkt->size < 12 + s->multichannel * 4)
+    if (avpkt->size <= WV_HEADER_SIZE)
         return AVERROR_INVALIDDATA;
 
     s->block     = 0;
@@ -1157,13 +1159,8 @@ static int wavpack_decode_frame(AVCodecContext *avctx, void *data,
         buf        += 4;
         frame_flags = AV_RL32(buf);
     } else {
-        if (s->multichannel) {
-            s->samples  = AV_RL32(buf + 4);
-            frame_flags = AV_RL32(buf + 8);
-        } else {
-            s->samples  = AV_RL32(buf);
-            frame_flags = AV_RL32(buf + 4);
-        }
+        s->samples  = AV_RL32(buf + 20);
+        frame_flags = AV_RL32(buf + 24);
     }
     if (s->samples <= 0) {
         av_log(avctx, AV_LOG_ERROR, "Invalid number of samples: %d\n",
@@ -1188,18 +1185,16 @@ static int wavpack_decode_frame(AVCodecContext *avctx, void *data,
     }
 
     while (buf_size > 0) {
-        if (!s->multichannel) {
-            frame_size = buf_size;
+        if (!s->mkv_mode) {
+            if (buf_size <= WV_HEADER_SIZE)
+                break;
+            frame_size = AV_RL32(buf + 4) - 12;
+            buf       += 20;
+            buf_size  -= 20;
         } else {
-            if (!s->mkv_mode) {
-                frame_size = AV_RL32(buf) - 12;
-                buf       += 4;
-                buf_size  -= 4;
-            } else {
-                if (buf_size < 12) // MKV files can have zero flags after last block
-                    break;
-                frame_size = AV_RL32(buf + 8) + 12;
-            }
+            if (buf_size < 12) // MKV files can have zero flags after last block
+                break;
+            frame_size = AV_RL32(buf + 8) + 12;
         }
         if (frame_size <= 0 || frame_size > buf_size) {
             av_log(avctx, AV_LOG_ERROR,
diff --git a/libavformat/wv.c b/libavformat/wv.c
index f6b96d5..3e09000 100644
--- a/libavformat/wv.c
+++ b/libavformat/wv.c
@@ -30,7 +30,7 @@
 // specs say that maximum block size is 1Mb
 #define WV_BLOCK_LIMIT 1047576
 
-#define WV_EXTRA_SIZE 12
+#define WV_HEADER_SIZE 32
 
 #define WV_START_BLOCK  0x0800
 #define WV_END_BLOCK    0x1000
@@ -56,13 +56,13 @@ static const int wv_rates[16] = {
 };
 
 typedef struct {
+    uint8_t block_header[WV_HEADER_SIZE];
     uint32_t blksize, flags;
     int rate, chan, bpp;
     uint32_t chmask;
     uint32_t samples, soff;
     int multichannel;
     int block_parsed;
-    uint8_t extra[WV_EXTRA_SIZE];
     int64_t pos;
 
     int64_t apetag_start;
@@ -80,12 +80,11 @@ static int wv_probe(AVProbeData *p)
         return 0;
 }
 
-static int wv_read_block_header(AVFormatContext *ctx, AVIOContext *pb,
-                                int append)
+static int wv_read_block_header(AVFormatContext *ctx, AVIOContext *pb)
 {
     WVContext *wc = ctx->priv_data;
-    uint32_t tag, ver;
-    int size;
+    uint32_t ver;
+    int size, ret;
     int rate, bpp, chan;
     uint32_t chmask;
 
@@ -95,33 +94,30 @@ static int wv_read_block_header(AVFormatContext *ctx, AVIOContext *pb,
     if (wc->apetag_start && wc->pos >= wc->apetag_start)
         return AVERROR_EOF;
 
-    if (!append) {
-        tag = avio_rl32(pb);
-        if (tag != MKTAG('w', 'v', 'p', 'k'))
-            return AVERROR_INVALIDDATA;
-        size = avio_rl32(pb);
-        if (size < 24 || size > WV_BLOCK_LIMIT) {
-            av_log(ctx, AV_LOG_ERROR, "Incorrect block size %i\n", size);
-            return AVERROR_INVALIDDATA;
-        }
-        wc->blksize = size;
-        ver = avio_rl16(pb);
-        if (ver < 0x402 || ver > 0x410) {
-            av_log(ctx, AV_LOG_ERROR, "Unsupported version %03X\n", ver);
-            return AVERROR_PATCHWELCOME;
-        }
-        avio_r8(pb); // track no
-        avio_r8(pb); // track sub index
-        wc->samples = avio_rl32(pb); // total samples in file
-        wc->soff    = avio_rl32(pb); // offset in samples of current block
-        avio_read(pb, wc->extra, WV_EXTRA_SIZE);
-    } else {
-        size = wc->blksize;
+    ret = avio_read(pb, wc->block_header, WV_HEADER_SIZE);
+    if (ret != WV_HEADER_SIZE)
+        return (ret < 0) ? ret : AVERROR_EOF;
+
+    if (AV_RL32(wc->block_header) != MKTAG('w', 'v', 'p', 'k'))
+        return AVERROR_INVALIDDATA;
+
+    size = AV_RL32(wc->block_header + 4);
+    if (size < 24 || size > WV_BLOCK_LIMIT) {
+        av_log(ctx, AV_LOG_ERROR, "Incorrect block size %i\n", size);
+        return AVERROR_INVALIDDATA;
+    }
+    wc->blksize = size;
+    ver = AV_RL32(wc->block_header + 8);
+    if (ver < 0x402 || ver > 0x410) {
+        av_log(ctx, AV_LOG_ERROR, "Unsupported version %03X\n", ver);
+        return AVERROR_PATCHWELCOME;
     }
-    wc->flags = AV_RL32(wc->extra + 4);
+    wc->samples = AV_RL32(wc->block_header + 12); // total samples in file
+    wc->soff    = AV_RL32(wc->block_header + 16); // offset in samples of current block
+    wc->flags   = AV_RL32(wc->block_header + 24);
     /* Blocks with zero samples don't contain actual audio information
      * and should be ignored */
-    if (!AV_RN32(wc->extra))
+    if (!AV_RN32(wc->block_header + 20))
         return 0;
     // parse flags
     bpp    = ((wc->flags & 3) + 1) << 3;
@@ -235,9 +231,9 @@ static int wv_read_header(AVFormatContext *s)
 
     wc->block_parsed = 0;
     for (;;) {
-        if ((ret = wv_read_block_header(s, pb, 0)) < 0)
+        if ((ret = wv_read_block_header(s, pb)) < 0)
             return ret;
-        if (!AV_RN32(wc->extra))
+        if (!AV_RL32(wc->block_header + 20))
             avio_skip(pb, wc->blksize - 24);
         else
             break;
@@ -272,75 +268,49 @@ static int wv_read_packet(AVFormatContext *s, AVPacket *pkt)
 {
     WVContext *wc = s->priv_data;
     int ret;
-    int size, ver, off;
+    int off;
     int64_t pos;
     uint32_t block_samples;
 
     if (s->pb->eof_reached)
         return AVERROR_EOF;
     if (wc->block_parsed) {
-        if ((ret = wv_read_block_header(s, s->pb, 0)) < 0)
+        if ((ret = wv_read_block_header(s, s->pb)) < 0)
             return ret;
     }
 
     pos = wc->pos;
-    off = wc->multichannel ? 4 : 0;
-    if (av_new_packet(pkt, wc->blksize + WV_EXTRA_SIZE + off) < 0)
+    if (av_new_packet(pkt, wc->blksize + WV_HEADER_SIZE) < 0)
         return AVERROR(ENOMEM);
-    if (wc->multichannel)
-        AV_WL32(pkt->data, wc->blksize + WV_EXTRA_SIZE + 12);
-    memcpy(pkt->data + off, wc->extra, WV_EXTRA_SIZE);
-    ret = avio_read(s->pb, pkt->data + WV_EXTRA_SIZE + off, wc->blksize);
+    memcpy(pkt->data, wc->block_header, WV_HEADER_SIZE);
+    ret = avio_read(s->pb, pkt->data + WV_HEADER_SIZE, wc->blksize);
     if (ret != wc->blksize) {
         av_free_packet(pkt);
         return AVERROR(EIO);
     }
     while (!(wc->flags & WV_END_BLOCK)) {
-        if (avio_rl32(s->pb) != MKTAG('w', 'v', 'p', 'k')) {
-            av_free_packet(pkt);
-            return AVERROR_INVALIDDATA;
-        }
-        if ((ret = av_append_packet(s->pb, pkt, 4)) < 0) {
+        if ((ret = wv_read_block_header(s, s->pb)) < 0) {
             av_free_packet(pkt);
             return ret;
         }
-        size = AV_RL32(pkt->data + pkt->size - 4);
-        if (size < 24 || size > WV_BLOCK_LIMIT) {
-            av_free_packet(pkt);
-            av_log(s, AV_LOG_ERROR, "Incorrect block size %d\n", size);
-            return AVERROR_INVALIDDATA;
-        }
-        wc->blksize = size;
-        ver         = avio_rl16(s->pb);
-        if (ver < 0x402 || ver > 0x410) {
-            av_free_packet(pkt);
-            av_log(s, AV_LOG_ERROR, "Unsupported version %03X\n", ver);
-            return AVERROR_PATCHWELCOME;
-        }
-        avio_r8(s->pb); // track no
-        avio_r8(s->pb); // track sub index
-        wc->samples = avio_rl32(s->pb); // total samples in file
-        wc->soff    = avio_rl32(s->pb); // offset in samples of current block
-        if ((ret = av_append_packet(s->pb, pkt, WV_EXTRA_SIZE)) < 0) {
-            av_free_packet(pkt);
-            return ret;
-        }
-        memcpy(wc->extra, pkt->data + pkt->size - WV_EXTRA_SIZE, WV_EXTRA_SIZE);
 
-        if ((ret = wv_read_block_header(s, s->pb, 1)) < 0) {
+        off = pkt->size;
+        if ((ret = av_grow_packet(pkt, WV_HEADER_SIZE + wc->blksize)) < 0) {
             av_free_packet(pkt);
             return ret;
         }
-        ret = av_append_packet(s->pb, pkt, wc->blksize);
-        if (ret < 0) {
+        memcpy(pkt->data + off, wc->block_header, WV_HEADER_SIZE);
+
+        ret = avio_read(s->pb, pkt->data + off + WV_HEADER_SIZE, wc->blksize);
+        if (ret != wc->blksize) {
             av_free_packet(pkt);
-            return ret;
+            return (ret < 0) ? ret : AVERROR_EOF;
         }
     }
     pkt->stream_index = 0;
     wc->block_parsed  = 1;
     pkt->pts          = wc->soff;
-    block_samples     = AV_RN32(wc->extra);
+    block_samples     = AV_RL32(wc->block_header + 20);
     if (block_samples > INT32_MAX)
         av_log(s, AV_LOG_WARNING,
                "Too many samples in block: %"PRIu32"\n", block_samples);



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