| /* |
| * MJPEG A dump header bitstream filter |
| * Copyright (c) 2006 Baptiste Coudurier |
| * |
| * This file is part of FFmpeg. |
| * |
| * FFmpeg is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Lesser General Public |
| * License as published by the Free Software Foundation; either |
| * version 2.1 of the License, or (at your option) any later version. |
| * |
| * FFmpeg is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * Lesser General Public License for more details. |
| * |
| * You should have received a copy of the GNU Lesser General Public |
| * License along with FFmpeg; if not, write to the Free Software |
| * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| */ |
| |
| /** |
| * @file |
| * MJPEG A dump header bitstream filter |
| * modifies bitstream to be decoded by quicktime |
| */ |
| |
| #include "bsf.h" |
| #include "bsf_internal.h" |
| #include "bytestream.h" |
| #include "mjpeg.h" |
| |
| |
| static int mjpega_dump_header(AVBSFContext *ctx, AVPacket *out) |
| { |
| AVPacket *in; |
| uint8_t *out_buf; |
| unsigned dqt = 0, dht = 0, sof0 = 0; |
| int ret = 0, i; |
| |
| ret = ff_bsf_get_packet(ctx, &in); |
| if (ret < 0) |
| return ret; |
| |
| ret = av_new_packet(out, in->size + 44); |
| if (ret < 0) |
| goto fail; |
| |
| ret = av_packet_copy_props(out, in); |
| if (ret < 0) |
| goto fail; |
| |
| out_buf = out->data; |
| bytestream_put_byte(&out_buf, 0xff); |
| bytestream_put_byte(&out_buf, SOI); |
| bytestream_put_byte(&out_buf, 0xff); |
| bytestream_put_byte(&out_buf, APP1); |
| bytestream_put_be16(&out_buf, 42); /* size */ |
| bytestream_put_be32(&out_buf, 0); |
| bytestream_put_buffer(&out_buf, "mjpg", 4); |
| bytestream_put_be32(&out_buf, in->size + 44); /* field size */ |
| bytestream_put_be32(&out_buf, in->size + 44); /* pad field size */ |
| bytestream_put_be32(&out_buf, 0); /* next ptr */ |
| |
| for (i = 0; i < in->size - 1; i++) { |
| if (in->data[i] == 0xff) { |
| switch (in->data[i + 1]) { |
| case DQT: dqt = i + 46; break; |
| case DHT: dht = i + 46; break; |
| case SOF0: sof0 = i + 46; break; |
| case SOS: |
| bytestream_put_be32(&out_buf, dqt); /* quant off */ |
| bytestream_put_be32(&out_buf, dht); /* huff off */ |
| bytestream_put_be32(&out_buf, sof0); /* image off */ |
| bytestream_put_be32(&out_buf, i + 46); /* scan off */ |
| bytestream_put_be32(&out_buf, i + 46 + AV_RB16(in->data + i + 2)); /* data off */ |
| bytestream_put_buffer(&out_buf, in->data + 2, in->size - 2); /* skip already written SOI */ |
| |
| out->size = out_buf - out->data; |
| av_packet_free(&in); |
| return 0; |
| case APP1: |
| if (i + 8 < in->size && AV_RL32(in->data + i + 8) == AV_RL32("mjpg")) { |
| av_log(ctx, AV_LOG_ERROR, "bitstream already formatted\n"); |
| av_packet_unref(out); |
| av_packet_move_ref(out, in); |
| av_packet_free(&in); |
| return 0; |
| } |
| } |
| } |
| } |
| av_log(ctx, AV_LOG_ERROR, "could not find SOS marker in bitstream\n"); |
| fail: |
| av_packet_unref(out); |
| av_packet_free(&in); |
| return AVERROR_INVALIDDATA; |
| } |
| |
| static const enum AVCodecID codec_ids[] = { |
| AV_CODEC_ID_MJPEG, AV_CODEC_ID_NONE, |
| }; |
| |
| const AVBitStreamFilter ff_mjpega_dump_header_bsf = { |
| .name = "mjpegadump", |
| .filter = mjpega_dump_header, |
| .codec_ids = codec_ids, |
| }; |