| 1 | /* |
| 2 | * MJPEG/AVI1 to JPEG/JFIF bitstream format filter |
| 3 | * Copyright (c) 2010 Adrian Daerr and Nicolas George |
| 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 | * Adapted from mjpeg2jpeg.c, with original copyright: |
| 24 | * Paris 2010 Adrian Daerr, public domain |
| 25 | */ |
| 26 | |
| 27 | #include <string.h> |
| 28 | |
| 29 | #include "libavutil/error.h" |
| 30 | #include "libavutil/mem.h" |
| 31 | |
| 32 | #include "avcodec.h" |
| 33 | #include "mjpeg.h" |
| 34 | |
| 35 | static const uint8_t jpeg_header[] = { |
| 36 | 0xff, 0xd8, // SOI |
| 37 | 0xff, 0xe0, // APP0 |
| 38 | 0x00, 0x10, // APP0 header size (including |
| 39 | // this field, but excluding preceding) |
| 40 | 0x4a, 0x46, 0x49, 0x46, 0x00, // ID string 'JFIF\0' |
| 41 | 0x01, 0x01, // version |
| 42 | 0x00, // bits per type |
| 43 | 0x00, 0x00, // X density |
| 44 | 0x00, 0x00, // Y density |
| 45 | 0x00, // X thumbnail size |
| 46 | 0x00, // Y thumbnail size |
| 47 | }; |
| 48 | |
| 49 | static const int dht_segment_size = 420; |
| 50 | static const uint8_t dht_segment_head[] = { 0xFF, 0xC4, 0x01, 0xA2, 0x00 }; |
| 51 | static const uint8_t dht_segment_frag[] = { |
| 52 | 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, |
| 53 | 0x0a, 0x0b, 0x01, 0x00, 0x03, 0x01, 0x01, 0x01, 0x01, 0x01, |
| 54 | 0x01, 0x01, 0x01, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, |
| 55 | }; |
| 56 | |
| 57 | static uint8_t *append(uint8_t *buf, const uint8_t *src, int size) |
| 58 | { |
| 59 | memcpy(buf, src, size); |
| 60 | return buf + size; |
| 61 | } |
| 62 | |
| 63 | static uint8_t *append_dht_segment(uint8_t *buf) |
| 64 | { |
| 65 | buf = append(buf, dht_segment_head, sizeof(dht_segment_head)); |
| 66 | buf = append(buf, avpriv_mjpeg_bits_dc_luminance + 1, 16); |
| 67 | buf = append(buf, dht_segment_frag, sizeof(dht_segment_frag)); |
| 68 | buf = append(buf, avpriv_mjpeg_val_dc, 12); |
| 69 | *(buf++) = 0x10; |
| 70 | buf = append(buf, avpriv_mjpeg_bits_ac_luminance + 1, 16); |
| 71 | buf = append(buf, avpriv_mjpeg_val_ac_luminance, 162); |
| 72 | *(buf++) = 0x11; |
| 73 | buf = append(buf, avpriv_mjpeg_bits_ac_chrominance + 1, 16); |
| 74 | buf = append(buf, avpriv_mjpeg_val_ac_chrominance, 162); |
| 75 | return buf; |
| 76 | } |
| 77 | |
| 78 | static int mjpeg2jpeg_filter(AVBitStreamFilterContext *bsfc, |
| 79 | AVCodecContext *avctx, const char *args, |
| 80 | uint8_t **poutbuf, int *poutbuf_size, |
| 81 | const uint8_t *buf, int buf_size, |
| 82 | int keyframe) |
| 83 | { |
| 84 | int input_skip, output_size; |
| 85 | uint8_t *output, *out; |
| 86 | |
| 87 | if (buf_size < 12) { |
| 88 | av_log(avctx, AV_LOG_ERROR, "input is truncated\n"); |
| 89 | return AVERROR_INVALIDDATA; |
| 90 | } |
| 91 | if (memcmp("AVI1", buf + 6, 4)) { |
| 92 | av_log(avctx, AV_LOG_ERROR, "input is not MJPEG/AVI1\n"); |
| 93 | return AVERROR_INVALIDDATA; |
| 94 | } |
| 95 | input_skip = (buf[4] << 8) + buf[5] + 4; |
| 96 | if (buf_size < input_skip) { |
| 97 | av_log(avctx, AV_LOG_ERROR, "input is truncated\n"); |
| 98 | return AVERROR_INVALIDDATA; |
| 99 | } |
| 100 | output_size = buf_size - input_skip + |
| 101 | sizeof(jpeg_header) + dht_segment_size; |
| 102 | output = out = av_malloc(output_size); |
| 103 | if (!output) |
| 104 | return AVERROR(ENOMEM); |
| 105 | out = append(out, jpeg_header, sizeof(jpeg_header)); |
| 106 | out = append_dht_segment(out); |
| 107 | out = append(out, buf + input_skip, buf_size - input_skip); |
| 108 | *poutbuf = output; |
| 109 | *poutbuf_size = output_size; |
| 110 | return 1; |
| 111 | } |
| 112 | |
| 113 | AVBitStreamFilter ff_mjpeg2jpeg_bsf = { |
| 114 | .name = "mjpeg2jpeg", |
| 115 | .filter = mjpeg2jpeg_filter, |
| 116 | }; |