[Ffmpeg-cvslog] r7738 - trunk/libavcodec/cook.c
banan
subversion
Sun Jan 28 11:05:21 CET 2007
Author: banan
Date: Sun Jan 28 11:05:21 2007
New Revision: 7738
Modified:
trunk/libavcodec/cook.c
Log:
Cook stereo (MONO_COOK2) bugfix, by Ian Braithwaite.
ian at braithwaite dot dk.
Modified: trunk/libavcodec/cook.c
==============================================================================
--- trunk/libavcodec/cook.c (original)
+++ trunk/libavcodec/cook.c Sun Jan 28 11:05:21 2007
@@ -277,16 +277,30 @@
/**
* Cook indata decoding, every 32 bits are XORed with 0x37c511f2.
* Why? No idea, some checksum/error detection method maybe.
+ *
+ * Out buffer size: extra bytes are needed to cope with
+ * padding/missalignment.
+ * Subpackets passed to the decoder can contain two, consecutive
+ * half-subpackets, of identical but arbitrary size.
+ * 1234 1234 1234 1234 extraA extraB
+ * Case 1: AAAA BBBB 0 0
+ * Case 2: AAAA ABBB BB-- 3 3
+ * Case 3: AAAA AABB BBBB 2 2
+ * Case 4: AAAA AAAB BBBB BB-- 1 5
+ *
* Nice way to waste CPU cycles.
*
- * @param in pointer to 32bit array of indata
- * @param bits amount of bits
- * @param out pointer to 32bit array of outdata
+ * @param inbuffer pointer to byte array of indata
+ * @param out pointer to byte array of outdata
+ * @param bytes number of bytes
*/
+#define DECODE_BYTES_PAD1(bytes) (3 - ((bytes)+3) % 4)
+#define DECODE_BYTES_PAD2(bytes) ((bytes) % 4 + DECODE_BYTES_PAD1(2 * (bytes)))
-static inline void decode_bytes(uint8_t* inbuffer, uint8_t* out, int bytes){
- int i;
- uint32_t* buf = (uint32_t*) inbuffer;
+static inline int decode_bytes(uint8_t* inbuffer, uint8_t* out, int bytes){
+ int i, off;
+ uint32_t c;
+ uint32_t* buf;
uint32_t* obuf = (uint32_t*) out;
/* FIXME: 64 bit platforms would be able to do 64 bits at a time.
* I'm too lazy though, should be something like
@@ -294,14 +308,14 @@
* (int64_t)out[i] = 0x37c511f237c511f2^be2me_64(int64_t)in[i]);
* Buffer alignment needs to be checked. */
+ off = (uint32_t)inbuffer % 4;
+ buf = (uint32_t*) (inbuffer - off);
+ c = be2me_32((0x37c511f2 >> (off*8)) | (0x37c511f2 << (32-(off*8))));
+ bytes += 3 + off;
+ for (i = 0; i < bytes/4; i++)
+ obuf[i] = c ^ buf[i];
- for(i=0 ; i<bytes/4 ; i++){
-#ifdef WORDS_BIGENDIAN
- obuf[i] = 0x37c511f2^buf[i];
-#else
- obuf[i] = 0xf211c537^buf[i];
-#endif
- }
+ return off;
}
/**
@@ -948,6 +962,28 @@
}
/**
+ * First part of subpacket decoding:
+ * decode raw stream bytes and read gain info.
+ *
+ * @param q pointer to the COOKContext
+ * @param inbuffer pointer to raw stream data
+ * @param gain_ptr array of current/prev gain pointers
+ */
+
+static inline void
+decode_bytes_and_gain(COOKContext *q, uint8_t *inbuffer, COOKgain *gain_ptr)
+{
+ int offset;
+
+ offset = decode_bytes(inbuffer, q->decoded_bytes_buffer,
+ q->bits_per_subpacket/8);
+ init_get_bits(&q->gb, q->decoded_bytes_buffer + offset,
+ q->bits_per_subpacket);
+ decode_gain_info(&q->gb, gain_ptr);
+}
+
+
+/**
* Cook subpacket decoding. This function returns one decoded subpacket,
* usually 1024 samples per channel.
*
@@ -970,11 +1006,9 @@
// }
// av_log(NULL, AV_LOG_ERROR, "\n");
- decode_bytes(inbuffer, q->decoded_bytes_buffer, sub_packet_size);
- init_get_bits(&q->gb, q->decoded_bytes_buffer, sub_packet_size*8);
- decode_gain_info(&q->gb, &q->gain_current);
-
if(q->nb_channels==2 && q->joint_stereo==1){
+ decode_bytes_and_gain(q, inbuffer, &q->gain_current);
+
joint_decode(q, q->decode_buf_ptr[0], q->decode_buf_ptr[2]);
/* Swap buffer pointers. */
@@ -1014,6 +1048,8 @@
} else if (q->nb_channels==2 && q->joint_stereo==0) {
/* channel 0 */
+ decode_bytes_and_gain(q, inbuffer, &q->gain_current);
+
mono_decode(q, q->decode_buf_ptr2[0]);
tmp_ptr = q->decode_buf_ptr2[0];
@@ -1035,17 +1071,17 @@
value = lrintf(q->mono_mdct_output[j]);
if(value < -32768) value = -32768;
else if(value > 32767) value = 32767;
- outbuffer[2*j+1] = value;
+ outbuffer[2*j] = value;
}
/* channel 1 */
//av_log(NULL,AV_LOG_ERROR,"bits = %d\n",get_bits_count(&q->gb));
- init_get_bits(&q->gb, q->decoded_bytes_buffer, sub_packet_size*8+q->bits_per_subpacket);
+ decode_bytes_and_gain(q, inbuffer + sub_packet_size/2,
+ &q->gain_channel2[0]);
q->gain_now_ptr = &q->gain_channel2[0];
q->gain_previous_ptr = &q->gain_channel2[1];
- decode_gain_info(&q->gb, &q->gain_channel2[0]);
mono_decode(q, q->decode_buf_ptr[0]);
tmp_ptr = q->decode_buf_ptr[0];
@@ -1067,10 +1103,12 @@
value = lrintf(q->mono_mdct_output[j]);
if(value < -32768) value = -32768;
else if(value > 32767) value = 32767;
- outbuffer[2*j] = value;
+ outbuffer[2*j+1] = value;
}
} else {
+ decode_bytes_and_gain(q, inbuffer, &q->gain_current);
+
mono_decode(q, q->decode_buf_ptr[0]);
/* Swap buffer pointers. */
@@ -1258,9 +1296,21 @@
if(avctx->block_align >= UINT_MAX/2)
return -1;
- /* Pad the databuffer with FF_INPUT_BUFFER_PADDING_SIZE,
- this is for the bitstreamreader. */
- if ((q->decoded_bytes_buffer = av_mallocz((avctx->block_align+(4-avctx->block_align%4) + FF_INPUT_BUFFER_PADDING_SIZE)*sizeof(uint8_t))) == NULL)
+ /* Pad the databuffer with:
+ DECODE_BYTES_PAD1 or DECODE_BYTES_PAD2 for decode_bytes(),
+ FF_INPUT_BUFFER_PADDING_SIZE, for the bitstreamreader. */
+ if (q->nb_channels==2 && q->joint_stereo==0) {
+ q->decoded_bytes_buffer =
+ av_mallocz(avctx->block_align/2
+ + DECODE_BYTES_PAD2(avctx->block_align/2)
+ + FF_INPUT_BUFFER_PADDING_SIZE);
+ } else {
+ q->decoded_bytes_buffer =
+ av_mallocz(avctx->block_align
+ + DECODE_BYTES_PAD1(avctx->block_align)
+ + FF_INPUT_BUFFER_PADDING_SIZE);
+ }
+ if (q->decoded_bytes_buffer == NULL)
return -1;
q->decode_buf_ptr[0] = q->decode_buffer_1;
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