Libav
mjpegenc.c
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1 /*
2  * MJPEG encoder
3  * Copyright (c) 2000, 2001 Fabrice Bellard
4  * Copyright (c) 2003 Alex Beregszaszi
5  * Copyright (c) 2003-2004 Michael Niedermayer
6  *
7  * Support for external huffman table, various fixes (AVID workaround),
8  * aspecting, new decode_frame mechanism and apple mjpeg-b support
9  * by Alex Beregszaszi
10  *
11  * This file is part of Libav.
12  *
13  * Libav is free software; you can redistribute it and/or
14  * modify it under the terms of the GNU Lesser General Public
15  * License as published by the Free Software Foundation; either
16  * version 2.1 of the License, or (at your option) any later version.
17  *
18  * Libav is distributed in the hope that it will be useful,
19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
21  * Lesser General Public License for more details.
22  *
23  * You should have received a copy of the GNU Lesser General Public
24  * License along with Libav; if not, write to the Free Software
25  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
26  */
27 
33 #include <assert.h>
34 
35 #include "libavutil/pixdesc.h"
36 
37 #include "avcodec.h"
38 #include "mjpegenc_common.h"
39 #include "mpegvideo.h"
40 #include "mjpeg.h"
41 #include "mjpegenc.h"
42 
44 {
45  MJpegContext *m;
46 
47  m = av_malloc(sizeof(MJpegContext));
48  if (!m)
49  return AVERROR(ENOMEM);
50 
51  s->min_qcoeff=-1023;
52  s->max_qcoeff= 1023;
53 
54  /* build all the huffman tables */
71 
72  s->mjpeg_ctx = m;
73  return 0;
74 }
75 
77 {
78  av_free(s->mjpeg_ctx);
79 }
80 
81 static void encode_block(MpegEncContext *s, int16_t *block, int n)
82 {
83  int mant, nbits, code, i, j;
84  int component, dc, run, last_index, val;
85  MJpegContext *m = s->mjpeg_ctx;
86  uint8_t *huff_size_ac;
87  uint16_t *huff_code_ac;
88 
89  /* DC coef */
90  component = (n <= 3 ? 0 : (n&1) + 1);
91  dc = block[0]; /* overflow is impossible */
92  val = dc - s->last_dc[component];
93  if (n < 4) {
95  huff_size_ac = m->huff_size_ac_luminance;
96  huff_code_ac = m->huff_code_ac_luminance;
97  } else {
99  huff_size_ac = m->huff_size_ac_chrominance;
100  huff_code_ac = m->huff_code_ac_chrominance;
101  }
102  s->last_dc[component] = dc;
103 
104  /* AC coefs */
105 
106  run = 0;
107  last_index = s->block_last_index[n];
108  for(i=1;i<=last_index;i++) {
109  j = s->intra_scantable.permutated[i];
110  val = block[j];
111  if (val == 0) {
112  run++;
113  } else {
114  while (run >= 16) {
115  put_bits(&s->pb, huff_size_ac[0xf0], huff_code_ac[0xf0]);
116  run -= 16;
117  }
118  mant = val;
119  if (val < 0) {
120  val = -val;
121  mant--;
122  }
123 
124  nbits= av_log2(val) + 1;
125  code = (run << 4) | nbits;
126 
127  put_bits(&s->pb, huff_size_ac[code], huff_code_ac[code]);
128 
129  put_sbits(&s->pb, nbits, mant);
130  run = 0;
131  }
132  }
133 
134  /* output EOB only if not already 64 values */
135  if (last_index < 63 || run != 0)
136  put_bits(&s->pb, huff_size_ac[0], huff_code_ac[0]);
137 }
138 
139 void ff_mjpeg_encode_mb(MpegEncContext *s, int16_t block[6][64])
140 {
141  int i;
142  for(i=0;i<5;i++) {
143  encode_block(s, block[i], i);
144  }
145  if (s->chroma_format == CHROMA_420) {
146  encode_block(s, block[5], 5);
147  } else {
148  encode_block(s, block[6], 6);
149  encode_block(s, block[5], 5);
150  encode_block(s, block[7], 7);
151  }
152 
153  s->i_tex_bits += get_bits_diff(s);
154 }
155 
157  .name = "mjpeg",
158  .long_name = NULL_IF_CONFIG_SMALL("MJPEG (Motion JPEG)"),
159  .type = AVMEDIA_TYPE_VIDEO,
160  .id = AV_CODEC_ID_MJPEG,
161  .priv_data_size = sizeof(MpegEncContext),
163  .encode2 = ff_mpv_encode_picture,
165  .pix_fmts = (const enum AVPixelFormat[]){
167  },
168 };
void * av_malloc(size_t size)
Allocate a block of size bytes with alignment suitable for all memory accesses (including vectors if ...
Definition: mem.c:62
void ff_mjpeg_encode_mb(MpegEncContext *s, int16_t block[6][64])
Definition: mjpegenc.c:139
static void put_sbits(PutBitContext *pb, int n, int32_t value)
Definition: put_bits.h:172
const uint8_t avpriv_mjpeg_bits_ac_luminance[17]
Definition: mjpeg.c:73
MJPEG encoder.
int min_qcoeff
minimum encodable coefficient
Definition: mpegvideo.h:429
const uint8_t avpriv_mjpeg_bits_dc_chrominance[17]
Definition: mjpeg.c:70
mpegvideo header.
const uint8_t avpriv_mjpeg_bits_ac_chrominance[17]
Definition: mjpeg.c:99
av_cold int ff_mjpeg_encode_init(MpegEncContext *s)
Definition: mjpegenc.c:43
uint8_t permutated[64]
Definition: idctdsp.h:31
uint8_t run
Definition: svq3.c:146
AVCodec.
Definition: avcodec.h:2796
MJPEG encoder and decoder.
uint16_t huff_code_dc_chrominance[12]
Definition: mjpegenc.h:44
uint16_t huff_code_ac_luminance[256]
Definition: mjpegenc.h:47
uint8_t
#define av_cold
Definition: attributes.h:66
static void encode_block(MpegEncContext *s, int16_t *block, int n)
Definition: mjpegenc.c:81
#define CHROMA_420
Definition: mpegvideo.h:582
void ff_mjpeg_build_huffman_codes(uint8_t *huff_size, uint16_t *huff_code, const uint8_t *bits_table, const uint8_t *val_table)
Definition: mjpeg.c:127
planar YUV 4:2:2, 16bpp, full scale (JPEG), deprecated in favor of PIX_FMT_YUV422P and setting color_...
Definition: pixfmt.h:78
uint8_t huff_size_dc_chrominance[12]
Definition: mjpegenc.h:43
int max_qcoeff
maximum encodable coefficient
Definition: mpegvideo.h:430
static int get_bits_diff(MpegEncContext *s)
Definition: mpegvideo.h:770
uint16_t huff_code_ac_chrominance[256]
Definition: mjpegenc.h:49
AVCodec ff_mjpeg_encoder
Definition: mjpegenc.c:156
uint8_t huff_size_ac_luminance[256]
Definition: mjpegenc.h:46
void av_free(void *ptr)
Free a memory block which has been allocated with av_malloc(z)() or av_realloc(). ...
Definition: mem.c:186
int last_dc[3]
last DC values for MPEG1
Definition: mpegvideo.h:311
#define AVERROR(e)
Definition: error.h:43
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:150
uint8_t huff_size_ac_chrominance[256]
Definition: mjpegenc.h:48
const char * name
Name of the codec implementation.
Definition: avcodec.h:2803
static void put_bits(PutBitContext *s, int n, unsigned int value)
Write up to 31 bits into a bitstream.
Definition: put_bits.h:134
planar YUV 4:2:0, 12bpp, full scale (JPEG), deprecated in favor of PIX_FMT_YUV420P and setting color_...
Definition: pixfmt.h:77
const uint8_t avpriv_mjpeg_bits_dc_luminance[17]
Definition: mjpeg.c:65
const uint8_t avpriv_mjpeg_val_dc[12]
Definition: mjpeg.c:67
int block_last_index[12]
last non zero coefficient in block
Definition: mpegvideo.h:209
struct MJpegContext * mjpeg_ctx
Definition: mpegvideo.h:537
void ff_mjpeg_encode_dc(PutBitContext *pb, int val, uint8_t *huff_size, uint16_t *huff_code)
Libavcodec external API header.
void ff_mjpeg_encode_close(MpegEncContext *s)
Definition: mjpegenc.c:76
static void close(AVCodecParserContext *s)
Definition: h264_parser.c:490
ScanTable intra_scantable
Definition: mpegvideo.h:214
int ff_mpv_encode_init(AVCodecContext *avctx)
uint8_t pi<< 24) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_U8, uint8_t,(*(constuint8_t *) pi-0x80)*(1.0f/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_U8, uint8_t,(*(constuint8_t *) pi-0x80)*(1.0/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S16, int16_t,(*(constint16_t *) pi >>8)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S16, int16_t,*(constint16_t *) pi *(1.0f/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S16, int16_t,*(constint16_t *) pi *(1.0/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S32, int32_t,(*(constint32_t *) pi >>24)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S32, int32_t,*(constint32_t *) pi *(1.0f/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S32, int32_t,*(constint32_t *) pi *(1.0/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_FLT, float, av_clip_uint8(lrintf(*(constfloat *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_FLT, float, av_clip_int16(lrintf(*(constfloat *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_FLT, float, av_clipl_int32(llrintf(*(constfloat *) pi *(1U<< 31)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_DBL, double, av_clip_uint8(lrint(*(constdouble *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_DBL, double, av_clip_int16(lrint(*(constdouble *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_DBL, double, av_clipl_int32(llrint(*(constdouble *) pi *(1U<< 31))))#defineSET_CONV_FUNC_GROUP(ofmt, ifmt) staticvoidset_generic_function(AudioConvert *ac){}voidff_audio_convert_free(AudioConvert **ac){if(!*ac) return;ff_dither_free(&(*ac) ->dc);av_freep(ac);}AudioConvert *ff_audio_convert_alloc(AVAudioResampleContext *avr, enumAVSampleFormatout_fmt, enumAVSampleFormatin_fmt, intchannels, intsample_rate, intapply_map){AudioConvert *ac;intin_planar, out_planar;ac=av_mallocz(sizeof(*ac));if(!ac) returnNULL;ac->avr=avr;ac->out_fmt=out_fmt;ac->in_fmt=in_fmt;ac->channels=channels;ac->apply_map=apply_map;if(avr->dither_method!=AV_RESAMPLE_DITHER_NONE &&av_get_packed_sample_fmt(out_fmt)==AV_SAMPLE_FMT_S16 &&av_get_bytes_per_sample(in_fmt)>2){ac->dc=ff_dither_alloc(avr, out_fmt, in_fmt, channels, sample_rate, apply_map);if(!ac->dc){av_free(ac);returnNULL;}returnac;}in_planar=ff_sample_fmt_is_planar(in_fmt, channels);out_planar=ff_sample_fmt_is_planar(out_fmt, channels);if(in_planar==out_planar){ac->func_type=CONV_FUNC_TYPE_FLAT;ac->planes=in_planar?ac->channels:1;}elseif(in_planar) ac->func_type=CONV_FUNC_TYPE_INTERLEAVE;elseac->func_type=CONV_FUNC_TYPE_DEINTERLEAVE;set_generic_function(ac);if(ARCH_AARCH64) ff_audio_convert_init_aarch64(ac);if(ARCH_ARM) ff_audio_convert_init_arm(ac);if(ARCH_X86) ff_audio_convert_init_x86(ac);returnac;}intff_audio_convert(AudioConvert *ac, AudioData *out, AudioData *in){intuse_generic=1;intlen=in->nb_samples;intp;if(ac->dc){av_dlog(ac->avr,"%dsamples-audio_convert:%sto%s(dithered)\n", len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt));returnff_convert_dither(ac-> dc
MpegEncContext.
Definition: mpegvideo.h:204
const uint8_t avpriv_mjpeg_val_ac_luminance[]
Definition: mjpeg.c:75
uint16_t huff_code_dc_luminance[12]
Definition: mjpegenc.h:42
PutBitContext pb
bit output
Definition: mpegvideo.h:277
uint8_t huff_size_dc_luminance[12]
Definition: mjpegenc.h:41
int ff_mpv_encode_end(AVCodecContext *avctx)
static av_cold int init(AVCodecParserContext *s)
Definition: h264_parser.c:499
const uint8_t avpriv_mjpeg_val_ac_chrominance[]
Definition: mjpeg.c:102
#define av_log2
Definition: intmath.h:85
int ff_mpv_encode_picture(AVCodecContext *avctx, AVPacket *pkt, const AVFrame *frame, int *got_packet)
AVPixelFormat
Pixel format.
Definition: pixfmt.h:63
static int16_t block[64]
Definition: dct-test.c:88