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Support for external huffman table and various fixes by Alex Beregszaszi <alex@naxine.org>

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Originally committed as revision 429 to svn://svn.ffmpeg.org/ffmpeg/trunk
pull/126/head
Arpi 23 years ago
parent 2a2a98c0d1
commit e84c31dc88
2 changed files with 147 additions and 19 deletions
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  1. 11
      libavcodec/avcodec.h
  2. 155
      libavcodec/mjpeg.c

11
libavcodec/avcodec.h
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@ -5,8 +5,8 @@
#define LIBAVCODEC_VERSION_INT 0x000406
#define LIBAVCODEC_VERSION "0.4.6"
#define LIBAVCODEC_BUILD 4604
#define LIBAVCODEC_BUILD_STR "4604"
#define LIBAVCODEC_BUILD 4605
#define LIBAVCODEC_BUILD_STR "4605"
enum CodecID {
CODEC_ID_NONE,
@ -93,6 +93,7 @@ static const int Motion_Est_QTab[] = { 1, 4, 3, 6, 5, 2 };
#define CODEC_FLAG_INPUT_PRESERVED 0x0100
#define CODEC_FLAG_PASS1 0x0200 /* use internal 2pass ratecontrol in first pass mode */
#define CODEC_FLAG_PASS2 0x0400 /* use internal 2pass ratecontrol in second pass mode */
#define CODEC_FLAG_EXTERN_HUFF 0x1000 /* use external huffman table (for mjpeg) */
/* codec capabilities */
@ -110,6 +111,12 @@ typedef struct AVCodecContext {
int me_method; /* ME algorithm used for video coding */
/* extra data from parent application to codec, e.g. huffman table
for mjpeg */
/* the parent should allocate and free this buffer */
void *extradata;
int extradata_size;
/* video only */
int frame_rate; /* frames per sec multiplied by FRAME_RATE_BASE */
int width, height;

155
libavcodec/mjpeg.c
Unescape View File

@ -15,6 +15,9 @@
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
* Support for external huffman table and various fixed by
* Alex Beregszaszi <alex@naxine.org>
*/
//#define DEBUG
#include "avcodec.h"
@ -33,12 +36,87 @@ typedef struct MJpegContext {
UINT16 huff_code_ac_chrominance[256];
} MJpegContext;
#define SOF0 0xc0
#define SOI 0xd8
#define EOI 0xd9
#define DQT 0xdb
#define DHT 0xc4
#define SOS 0xda
/* JPEG marker codes */
typedef enum {
/* start of frame */
SOF0 = 0xc0, /* baseline */
SOF1 = 0xc1, /* extended sequential, huffman */
SOF2 = 0xc2, /* progressive, huffman */
SOF3 = 0xc3, /* lossless, huffman */
SOF5 = 0xc5, /* differential sequential, huffman */
SOF6 = 0xc6, /* differential progressive, huffman */
SOF7 = 0xc7, /* differential lossless, huffman */
JPG = 0xc8, /* reserved for JPEG extension */
SOF9 = 0xc9, /* extended sequential, arithmetic */
SOF10 = 0xca, /* progressive, arithmetic */
SOF11 = 0xcb, /* lossless, arithmetic */
SOF13 = 0xcd, /* differential sequential, arithmetic */
SOF14 = 0xce, /* differential progressive, arithmetic */
SOF15 = 0xcf, /* differential lossless, arithmetic */
DHT = 0xc4, /* define huffman tables */
DAC = 0xcc, /* define arithmetic-coding conditioning */
/* restart with modulo 8 count "m" */
RST0 = 0xd0,
RST1 = 0xd1,
RST2 = 0xd2,
RST3 = 0xd3,
RST4 = 0xd4,
RST5 = 0xd5,
RST6 = 0xd6,
RST7 = 0xd7,
SOI = 0xd8, /* start of image */
EOI = 0xd9, /* end of image */
SOS = 0xda, /* start of scan */
DQT = 0xdb, /* define quantization tables */
DNL = 0xdc, /* define number of lines */
DRI = 0xdd, /* define restart interval */
DHP = 0xde, /* define hierarchical progression */
EXP = 0xdf, /* expand reference components */
APP0 = 0xe0,
APP1 = 0xe1,
APP2 = 0xe2,
APP3 = 0xe3,
APP4 = 0xe4,
APP5 = 0xe5,
APP6 = 0xe6,
APP7 = 0xe7,
APP8 = 0xe8,
APP9 = 0xe9,
APP10 = 0xea,
APP11 = 0xeb,
APP12 = 0xec,
APP13 = 0xed,
APP14 = 0xee,
APP15 = 0xef,
JPG0 = 0xf0,
JPG1 = 0xf1,
JPG2 = 0xf2,
JPG3 = 0xf3,
JPG4 = 0xf4,
JPG5 = 0xf5,
JPG6 = 0xf6,
JPG7 = 0xf7,
JPG8 = 0xf8,
JPG9 = 0xf9,
JPG10 = 0xfa,
JPG11 = 0xfb,
JPG12 = 0xfc,
JPG13 = 0xfd,
COM = 0xfe, /* comment */
TEM = 0x01, /* temporary private use for arithmetic coding */
/* 0x02 -> 0xbf reserved */
} JPEG_MARKER;
#if 0
/* These are the sample quantization tables given in JPEG spec section K.1.
@ -487,6 +565,13 @@ static int mjpeg_decode_init(AVCodecContext *avctx)
build_vlc(&s->vlcs[0][1], bits_dc_chrominance, val_dc_chrominance, 12);
build_vlc(&s->vlcs[1][0], bits_ac_luminance, val_ac_luminance, 251);
build_vlc(&s->vlcs[1][1], bits_ac_chrominance, val_ac_chrominance, 251);
if (avctx->flags & CODEC_FLAG_EXTERN_HUFF)
{
printf("mjpeg: using external huffman table\n");
mjpeg_decode_dht(s, avctx->extradata, avctx->extradata_size);
/* should check for error - but dunno */
}
return 0;
}
@ -503,7 +588,10 @@ static int mjpeg_decode_dqt(MJpegDecodeContext *s,
while (len >= 65) {
/* only 8 bit precision handled */
if (get_bits(&s->gb, 4) != 0)
{
dprintf("dqt: 16bit precision\n");
return -1;
}
index = get_bits(&s->gb, 4);
if (index >= 4)
return -1;
@ -636,21 +724,26 @@ static int mjpeg_decode_sof0(MJpegDecodeContext *s,
}
s->first_picture = 0;
}
if (len != 8+(3*nb_components))
dprintf("decode_sof0: error, len(%d) mismatch\n", len);
return 0;
}
static inline int decode_dc(MJpegDecodeContext *s, int dc_index)
{
VLC *dc_vlc;
int code, diff;
dc_vlc = &s->vlcs[0][dc_index];
code = get_vlc(&s->gb, dc_vlc);
code = get_vlc(&s->gb, &s->vlcs[0][dc_index]);
if (code < 0)
{
dprintf("decode_dc: bad vlc: %d:%d\n", 0, dc_index);
return 0xffff;
}
if (code == 0) {
diff = 0;
// dprintf("decode_dc: bad code\n");
} else {
diff = get_bits(&s->gb, code);
if ((diff & (1 << (code - 1))) == 0)
@ -668,13 +761,13 @@ static int decode_block(MJpegDecodeContext *s, DCTELEM *block,
VLC *ac_vlc;
INT16 *quant_matrix;
quant_matrix = s->quant_matrixes[quant_index];
/* DC coef */
val = decode_dc(s, dc_index);
if (val == 0xffff) {
dprintf("error dc\n");
return -1;
}
quant_matrix = s->quant_matrixes[quant_index];
val = val * quant_matrix[0] + s->last_dc[component];
s->last_dc[component] = val;
block[0] = val;
@ -731,7 +824,10 @@ static int mjpeg_decode_sos(MJpegDecodeContext *s,
nb_components = get_bits(&s->gb, 8);
/* XXX: only interleaved scan accepted */
if (nb_components != 3)
{
dprintf("decode_sos: components(%d) mismatch\n", nb_components);
return -1;
}
vmax = 0;
hmax = 0;
for(i=0;i<nb_components;i++) {
@ -741,7 +837,10 @@ static int mjpeg_decode_sos(MJpegDecodeContext *s,
if (id == s->component_id[index])
break;
if (index == s->nb_components)
{
dprintf("decode_sos: index out of components\n");
return -1;
}
comp_index[i] = index;
nb_blocks[i] = s->h_count[index] * s->v_count[index];
@ -749,15 +848,31 @@ static int mjpeg_decode_sos(MJpegDecodeContext *s,
v_count[i] = s->v_count[index];
dc_index[i] = get_bits(&s->gb, 4);
if (dc_index[i] >= 4)
return -1;
ac_index[i] = get_bits(&s->gb, 4);
if (ac_index[i] >= 4)
return -1;
if (dc_index[i] < 0 || ac_index[i] < 0 ||
dc_index[i] >= 4 || ac_index[i] >= 4)
goto out_of_range;
switch(s->start_code)
{
case SOF0:
if (dc_index[i] > 1 || ac_index[i] > 1)
goto out_of_range;
break;
case SOF1:
case SOF2:
if (dc_index[i] > 3 || ac_index[i] > 3)
goto out_of_range;
break;
case SOF3:
if (dc_index[i] > 3 || ac_index[i] != 0)
goto out_of_range;
break;
}
}
get_bits(&s->gb, 8); /* Ss */
get_bits(&s->gb, 8); /* Se */
get_bits(&s->gb, 8); /* not used */
get_bits(&s->gb, 8); /* Ah and Al (each are 4 bits) */
for(i=0;i<nb_components;i++)
s->last_dc[i] = 1024;
@ -796,6 +911,7 @@ static int mjpeg_decode_sos(MJpegDecodeContext *s,
ret = -1;
goto the_end;
}
// dprintf("mb: %d %d processed\n", mb_y, mb_x);
ff_idct (s->block);
ptr = s->current_picture[c] +
(s->linesize[c] * (v * mb_y + y) * 8) +
@ -815,6 +931,9 @@ static int mjpeg_decode_sos(MJpegDecodeContext *s,
the_end:
emms_c();
return ret;
out_of_range:
dprintf("decode_sos: ac/dc index out of range\n");
return -1;
}
/* return the 8 bit start code value and update the search
@ -858,8 +977,9 @@ static int mjpeg_decode_frame(AVCodecContext *avctx,
{
MJpegDecodeContext *s = avctx->priv_data;
UINT8 *buf_end, *buf_ptr, *buf_start;
int len, code, start_code, input_size, i;
int len, code, input_size, i;
AVPicture *picture = data;
unsigned int start_code;
*data_size = 0;
@ -884,7 +1004,8 @@ static int mjpeg_decode_frame(AVCodecContext *avctx,
memcpy(s->buf_ptr, buf_start, len);
s->buf_ptr += len;
/* if we got FF 00, we copy FF to the stream to unescape FF 00 */
if (code == 0) {
/* valid marker code is between 00 and ff - alex */
if (code == 0 || code == 0xff) {
s->buf_ptr--;
} else if (code > 0) {
/* prepare data for next start code */

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