On 21/04/2025 01:54, Michael Niedermayer wrote:
> On Sat, Apr 19, 2025 at 08:07:00PM +0100, Mark Thompson wrote:
>> Demuxes raw streams as defined in draft spec section 10.2.
>> ---
>> libavformat/Makefile | 1 +
>> libavformat/allformats.c | 1 +
>> libavformat/apvdec.c | 245 +++++++++++++++++++++++++++++++++++++++
>> 3 files changed, 247 insertions(+)
>> create mode 100644 libavformat/apvdec.c
>>
>> diff --git a/libavformat/Makefile b/libavformat/Makefile
>> index a94ac66e7e..ef96c2762e 100644
>> --- a/libavformat/Makefile
>> +++ b/libavformat/Makefile
>> @@ -119,6 +119,7 @@ OBJS-$(CONFIG_APTX_DEMUXER) += aptxdec.o
>> OBJS-$(CONFIG_APTX_MUXER) += rawenc.o
>> OBJS-$(CONFIG_APTX_HD_DEMUXER) += aptxdec.o
>> OBJS-$(CONFIG_APTX_HD_MUXER) += rawenc.o
>> +OBJS-$(CONFIG_APV_DEMUXER) += apvdec.o
>> OBJS-$(CONFIG_AQTITLE_DEMUXER) += aqtitledec.o subtitles.o
>> OBJS-$(CONFIG_ARGO_ASF_DEMUXER) += argo_asf.o
>> OBJS-$(CONFIG_ARGO_ASF_MUXER) += argo_asf.o
>> diff --git a/libavformat/allformats.c b/libavformat/allformats.c
>> index 445f13f42a..90a4fe64ec 100644
>> --- a/libavformat/allformats.c
>> +++ b/libavformat/allformats.c
>> @@ -72,6 +72,7 @@ extern const FFInputFormat ff_aptx_demuxer;
>> extern const FFOutputFormat ff_aptx_muxer;
>> extern const FFInputFormat ff_aptx_hd_demuxer;
>> extern const FFOutputFormat ff_aptx_hd_muxer;
>> +extern const FFInputFormat ff_apv_demuxer;
>> extern const FFInputFormat ff_aqtitle_demuxer;
>> extern const FFInputFormat ff_argo_asf_demuxer;
>> extern const FFOutputFormat ff_argo_asf_muxer;
>> diff --git a/libavformat/apvdec.c b/libavformat/apvdec.c
>> new file mode 100644
>> index 0000000000..008cbef708
>> --- /dev/null
>> +++ b/libavformat/apvdec.c
>> @@ -0,0 +1,245 @@
>> +/*
>> + * 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
>> + */
>> +
>
>> +#include "libavcodec/apv.h"
>
> missing file
I will reorder the cbs patch before this one.
>> +#include "libavcodec/get_bits.h"
>> +#include "avformat.h"
>> +#include "avio_internal.h"
>> +#include "demux.h"
>> +#include "internal.h"
>> +
>> +
>> +#define APV_TAG MKBETAG('a', 'P', 'v', '1')
>> +
>> +typedef struct APVHeaderInfo {
>> + uint8_t pbu_type;
>> + uint16_t group_id;
>> +
>> + uint8_t profile_idc;
>> + uint8_t level_idc;
>> + uint8_t band_idc;
>> +
>> + uint32_t frame_width;
>> + uint32_t frame_height;
>> +
>> + uint8_t chroma_format_idc;
>> + uint8_t bit_depth_minus8;
>> +
>> + enum AVPixelFormat pixel_format;
>> +} APVHeaderInfo;
>> +
>> +static const enum AVPixelFormat apv_format_table[5][5] = {
>> + { AV_PIX_FMT_GRAY8, AV_PIX_FMT_GRAY10, AV_PIX_FMT_GRAY12,
>> AV_PIX_FMT_GRAY14, AV_PIX_FMT_GRAY16 },
>> + { 0 }, // 4:2:0 is not valid.
>> + { AV_PIX_FMT_YUV422P, AV_PIX_FMT_YUV422P10, AV_PIX_FMT_YUV422P12,
>> AV_PIX_FMT_GRAY14, AV_PIX_FMT_YUV422P16 },
>> + { AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUV444P10, AV_PIX_FMT_YUV444P12,
>> AV_PIX_FMT_GRAY14, AV_PIX_FMT_YUV444P16 },
>> + { AV_PIX_FMT_YUVA444P, AV_PIX_FMT_YUVA444P10, AV_PIX_FMT_YUVA444P12,
>> AV_PIX_FMT_GRAY14, AV_PIX_FMT_YUVA444P16 },
>> +};
>> +
>
>> +static int apv_extract_header_info(APVHeaderInfo *info,
>> + GetBitContext *gbc)
>> +{
>> + int zero, bit_depth_index;
>> +
>> + info->pbu_type = get_bits(gbc, 8);
>> + info->group_id = get_bits(gbc, 16);
>> +
>> + zero = get_bits(gbc, 8);
>> + if (zero != 0)
>> + return 0;
>
> this should use negative AVERROR* for errors for consistency
Ok.
>> +
>> + if (info->pbu_type != APV_PBU_PRIMARY_FRAME)
>> + return 0;
>> +
>> + info->profile_idc = get_bits(gbc, 8);
>> + info->level_idc = get_bits(gbc, 8);
>> + info->band_idc = get_bits(gbc, 3);
>> +
>> + zero = get_bits(gbc, 5);
>> + if (zero != 0)
>> + return 0;
>> +
>
>> + info->frame_width = get_bits(gbc, 24);
>> + info->frame_height = get_bits(gbc, 24);
>
> frame_width and frame_height would be better as int instead of uint32_t
> given its only 24bit
>
> its also more consistent
> git grep 'int *width' | wc
> 1935 15372 180444
>
> git grep 'uint32_t *width' | wc
> 15 62 740
Sure. We can change it to uint32_t later if there is a decision to use
APVDecoderConfigurationRecord directly.
> [...]
>> +static int apv_probe(const AVProbeData *p)
>> +{
>> + GetBitContext gbc;
>> + APVHeaderInfo header;
>> + uint32_t au_size, tag, pbu_size;
>> + int score = AVPROBE_SCORE_EXTENSION + 1;
>> + int ret;
>> +
>> + init_get_bits8(&gbc, p->buf, p->buf_size);
>> +
>> + au_size = get_bits_long(&gbc, 32);
>> + if (au_size < 16) {
Here ^
>> + // Too small.
>> + return 0;
>> + }
>> + // The spec doesn't have this tag, but the reference software and
>> + // all current files do. Treat it as optional and skip if present,
>> + // but if it is there then this is definitely an APV file.
>> + tag = get_bits_long(&gbc, 32);
>> + if (tag == APV_TAG) {
>> + pbu_size = get_bits_long(&gbc, 32);
>> + score = AVPROBE_SCORE_MAX;
>> + } else {
>> + pbu_size = tag;
>> + }
>> + if (pbu_size < 16) {
>> + // Too small.
>> + return 0;
>> + }
>> +
>> + ret = apv_extract_header_info(&header, &gbc);
>
> something somewhere should check buf_size or size in gbc
> otherwise a truncated header would be accepted
See check above.
Thanks,
- Mark
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