FFmpeg  4.0
mjpega_dump_header_bsf.c
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1 /*
2  * MJPEG A dump header bitstream filter
3  * Copyright (c) 2006 Baptiste Coudurier
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * MJPEG A dump header bitstream filter
25  * modifies bitstream to be decoded by quicktime
26  */
27 
28 #include "avcodec.h"
29 #include "bsf.h"
30 #include "bytestream.h"
31 #include "mjpeg.h"
32 
33 
35 {
36  AVPacket *in;
37  uint8_t *out_buf;
38  unsigned dqt = 0, dht = 0, sof0 = 0;
39  int ret = 0, i;
40 
41  ret = ff_bsf_get_packet(ctx, &in);
42  if (ret < 0)
43  return ret;
44 
45  ret = av_new_packet(out, in->size + 44);
46  if (ret < 0)
47  goto fail;
48 
49  ret = av_packet_copy_props(out, in);
50  if (ret < 0)
51  goto fail;
52 
53  out_buf = out->data;
54  bytestream_put_byte(&out_buf, 0xff);
55  bytestream_put_byte(&out_buf, SOI);
56  bytestream_put_byte(&out_buf, 0xff);
57  bytestream_put_byte(&out_buf, APP1);
58  bytestream_put_be16(&out_buf, 42); /* size */
59  bytestream_put_be32(&out_buf, 0);
60  bytestream_put_buffer(&out_buf, "mjpg", 4);
61  bytestream_put_be32(&out_buf, in->size + 44); /* field size */
62  bytestream_put_be32(&out_buf, in->size + 44); /* pad field size */
63  bytestream_put_be32(&out_buf, 0); /* next ptr */
64 
65  for (i = 0; i < in->size - 1; i++) {
66  if (in->data[i] == 0xff) {
67  switch (in->data[i + 1]) {
68  case DQT: dqt = i + 46; break;
69  case DHT: dht = i + 46; break;
70  case SOF0: sof0 = i + 46; break;
71  case SOS:
72  bytestream_put_be32(&out_buf, dqt); /* quant off */
73  bytestream_put_be32(&out_buf, dht); /* huff off */
74  bytestream_put_be32(&out_buf, sof0); /* image off */
75  bytestream_put_be32(&out_buf, i + 46); /* scan off */
76  bytestream_put_be32(&out_buf, i + 46 + AV_RB16(in->data + i + 2)); /* data off */
77  bytestream_put_buffer(&out_buf, in->data + 2, in->size - 2); /* skip already written SOI */
78 
79  out->size = out_buf - out->data;
80  av_packet_free(&in);
81  return 0;
82  case APP1:
83  if (i + 8 < in->size && AV_RL32(in->data + i + 8) == AV_RL32("mjpg")) {
84  av_log(ctx, AV_LOG_ERROR, "bitstream already formatted\n");
85  av_packet_unref(out);
86  av_packet_move_ref(out, in);
87  av_packet_free(&in);
88  return 0;
89  }
90  }
91  }
92  }
93  av_log(ctx, AV_LOG_ERROR, "could not find SOS marker in bitstream\n");
94 fail:
95  av_packet_unref(out);
96  av_packet_free(&in);
97  return AVERROR_INVALIDDATA;
98 }
99 
100 static const enum AVCodecID codec_ids[] = {
102 };
103 
105  .name = "mjpegadump",
106  .filter = mjpega_dump_header,
107  .codec_ids = codec_ids,
108 };
static enum AVCodecID codec_ids[]
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
Definition: mjpeg.h:73
The bitstream filter state.
Definition: avcodec.h:5687
int size
Definition: avcodec.h:1431
MJPEG encoder and decoder.
Definition: mjpeg.h:72
void av_packet_free(AVPacket **pkt)
Free the packet, if the packet is reference counted, it will be unreferenced first.
Definition: avpacket.c:62
uint8_t
const char * name
Definition: avcodec.h:5737
uint8_t * data
Definition: avcodec.h:1430
void av_packet_move_ref(AVPacket *dst, AVPacket *src)
Move every field in src to dst and reset src.
Definition: avpacket.c:647
#define av_log(a,...)
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:86
AVCodecID
Identify the syntax and semantics of the bitstream.
Definition: avcodec.h:215
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
#define AV_RB16
Definition: intreadwrite.h:53
#define fail()
Definition: checkasm.h:116
Definition: mjpeg.h:39
Definition: mjpeg.h:70
Definition: mjpeg.h:80
int av_packet_copy_props(AVPacket *dst, const AVPacket *src)
Copy only "properties" fields from src to dst.
Definition: avpacket.c:558
Definition: mjpeg.h:56
AVFormatContext * ctx
Definition: movenc.c:48
#define AV_RL32
Definition: intreadwrite.h:146
static int mjpega_dump_header(AVBSFContext *ctx, AVPacket *out)
Libavcodec external API header.
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:592
uint8_t pi<< 24) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_U8, uint8_t,(*(const uint8_t *) pi - 0x80) *(1.0f/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_U8, uint8_t,(*(const uint8_t *) pi - 0x80) *(1.0/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S16, int16_t,(*(const int16_t *) pi >> 8)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S16, int16_t, *(const int16_t *) pi *(1.0f/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S16, int16_t, *(const int16_t *) pi *(1.0/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S32, int32_t,(*(const int32_t *) pi >> 24)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S32, int32_t, *(const int32_t *) pi *(1.0f/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S32, int32_t, *(const int32_t *) pi *(1.0/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_FLT, float, av_clip_uint8(lrintf(*(const float *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_FLT, float, av_clip_int16(lrintf(*(const float *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_FLT, float, av_clipl_int32(llrintf(*(const float *) pi *(1U<< 31)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_DBL, double, av_clip_uint8(lrint(*(const double *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_DBL, double, av_clip_int16(lrint(*(const double *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_DBL, double, av_clipl_int32(llrint(*(const double *) pi *(1U<< 31)))) #define SET_CONV_FUNC_GROUP(ofmt, ifmt) static void set_generic_function(AudioConvert *ac) { } void ff_audio_convert_free(AudioConvert **ac) { if(! *ac) return;ff_dither_free(&(*ac) ->dc);av_freep(ac);} AudioConvert *ff_audio_convert_alloc(AVAudioResampleContext *avr, enum AVSampleFormat out_fmt, enum AVSampleFormat in_fmt, int channels, int sample_rate, int apply_map) { AudioConvert *ac;int in_planar, out_planar;ac=av_mallocz(sizeof(*ac));if(!ac) return NULL;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);return NULL;} return ac;} 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;} else if(in_planar) ac->func_type=CONV_FUNC_TYPE_INTERLEAVE;else ac->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);return ac;} int ff_audio_convert(AudioConvert *ac, AudioData *out, AudioData *in) { int use_generic=1;int len=in->nb_samples;int p;if(ac->dc) { av_log(ac->avr, AV_LOG_TRACE, "%d samples - audio_convert: %s to %s (dithered)\", len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt));return ff_convert_dither(ac-> in
int ff_bsf_get_packet(AVBSFContext *ctx, AVPacket **pkt)
Called by the bitstream filters to get the next packet for filtering.
Definition: bsf.c:206
static av_always_inline void bytestream_put_buffer(uint8_t **b, const uint8_t *src, unsigned int size)
Definition: bytestream.h:368
const AVBitStreamFilter ff_mjpega_dump_header_bsf
FILE * out
Definition: movenc.c:54
This structure stores compressed data.
Definition: avcodec.h:1407