[FFmpeg-devel] [PATCH v5] lavc/rawdec: Use AV_PIX_FMT_PAL8 for 1-bit raw AVI video, and more
Mats Peterson
matsp888 at yahoo.com
Mon Jan 25 01:28:17 CET 2016
On 01/25/2016 01:23 AM, Mats Peterson wrote:
> On 01/25/2016 01:14 AM, Michael Niedermayer wrote:
>> On Fri, Jan 22, 2016 at 03:44:30PM +0100, Mats Peterson wrote:
>>> You'll have to excuse me, Michael, but the changes I've made,
>>> including the line alignment changes, are dependent on each other,
>>> and not easy or very logical to split. Here's a new version that
>>> displays the Matrix video correctly.
>>>
>>> Mats
>>>
>>> --
>>> Mats Peterson
>>> http://matsp888.no-ip.org/~mats/
>>
>>> raw.c | 2 -
>>> rawdec.c | 92
>>> +++++++++++++++++++++++++++++++++++++++++----------------------
>>> 2 files changed, 62 insertions(+), 32 deletions(-)
>>> 7e3ead59067fc542c5ad6c3231ab5783bad57c0b
>>> 0001-lavc-rawdec-Use-AV_PIX_FMT_PAL8-for-1-bit-raw-AVI-vi.patch
>>> From 0f99c5bdcf39230556eef82fa849dd6342208539 Mon Sep 17 00:00:00 2001
>>> From: Mats Peterson <matsp888 at yahoo.com>
>>> Date: Fri, 22 Jan 2016 15:38:26 +0100
>>> Subject: [PATCH v5] lavc/rawdec: Use AV_PIX_FMT_PAL8 for 1-bit raw
>>> AVI video, and more
>>>
>>> The stuff about 1-bit video not necessarily being black & white in
>>> QuickTime goes for AVI as well. Being 1 bit per pixel only means that
>>> the data is bi-level. The two colors can be any color. Since many
>>> 1 bpp AVI files don't have a palette following the BITMAPINFOHEADER,
>>> I'm setting a "default" black & white palette in raw_init_decoder().
>>>
>>> Also, the line alignment for 4 bpp and 8 bpp depths generated warning
>>> messages. The line alignment is now 16 bytes for 1, 2, 4, and 8 bpp
>>> depth.
>>>
>>> Mats
>>>
>>> ---
>>> libavcodec/raw.c | 2 +-
>>> libavcodec/rawdec.c | 92
>>> ++++++++++++++++++++++++++++++++++-----------------
>>> 2 files changed, 62 insertions(+), 32 deletions(-)
>>>
>>> diff --git a/libavcodec/raw.c b/libavcodec/raw.c
>>> index 3f2cc11..3979c5c 100644
>>> --- a/libavcodec/raw.c
>>> +++ b/libavcodec/raw.c
>>> @@ -242,7 +242,7 @@ unsigned int avcodec_pix_fmt_to_codec_tag(enum
>>> AVPixelFormat fmt)
>>> }
>>>
>>> const PixelFormatTag avpriv_pix_fmt_bps_avi[] = {
>>> - { AV_PIX_FMT_MONOWHITE, 1 },
>>> + { AV_PIX_FMT_PAL8, 1 },
>>> { AV_PIX_FMT_PAL8, 2 },
>>> { AV_PIX_FMT_PAL8, 4 },
>>> { AV_PIX_FMT_PAL8, 8 },
>>> diff --git a/libavcodec/rawdec.c b/libavcodec/rawdec.c
>>> index cb0364c..9c4e69a 100644
>>> --- a/libavcodec/rawdec.c
>>> +++ b/libavcodec/rawdec.c
>>> @@ -41,7 +41,7 @@ typedef struct RawVideoContext {
>>> AVBufferRef *palette;
>>> int frame_size; /* size of the frame in bytes */
>>> int flip;
>>> - int is_1_2_4_bpp; // 1 bpp raw in mov, and 2 or 4 bpp raw in
>>> avi/mov
>>> + int is_1_2_4_8_bpp; // 1, 2, 4 and 8 bpp raw in avi/mov
>>> int is_yuv2;
>>> int is_lt_16bpp; // 16bpp pixfmt and bits_per_coded_sample < 16
>>> int tff;
>>> @@ -94,8 +94,11 @@ static av_cold int raw_init_decoder(AVCodecContext
>>> *avctx)
>>> return AVERROR(ENOMEM);
>>> if (desc->flags & AV_PIX_FMT_FLAG_PSEUDOPAL)
>>>
>>> avpriv_set_systematic_pal2((uint32_t*)context->palette->data,
>>> avctx->pix_fmt);
>>> - else
>>> + else {
>>> memset(context->palette->data, 0, AVPALETTE_SIZE);
>>> + if (avctx->bits_per_coded_sample == 1)
>>> + memset(context->palette->data, 0xff, 4);
>>> + }
>>> }
>>>
>>> if ((avctx->extradata_size >= 9 &&
>>> @@ -153,19 +156,20 @@ static int raw_decode(AVCodecContext *avctx,
>>> void *data, int *got_frame,
>>> RawVideoContext *context = avctx->priv_data;
>>> const uint8_t *buf = avpkt->data;
>>> int buf_size = avpkt->size;
>>> + int avpkt_stride = avpkt->size / avctx->height;
>>> int linesize_align = 4;
>>> int res, len;
>>> int need_copy;
>>>
>>> AVFrame *frame = data;
>>>
>>> - if ((avctx->bits_per_coded_sample == 4 ||
>>> avctx->bits_per_coded_sample == 2
>>> - || avctx->bits_per_coded_sample == 1) &&
>>> + if ((avctx->bits_per_coded_sample == 8 ||
>>> avctx->bits_per_coded_sample == 4
>>> + || avctx->bits_per_coded_sample == 2 ||
>>> avctx->bits_per_coded_sample == 1) &&
>>> avctx->pix_fmt == AV_PIX_FMT_PAL8 &&
>>> (!avctx->codec_tag || avctx->codec_tag ==
>>> MKTAG('r','a','w',' '))) {
>>> - context->is_1_2_4_bpp = 1;
>>> + context->is_1_2_4_8_bpp = 1;
>>> context->frame_size = av_image_get_buffer_size(avctx->pix_fmt,
>>> -
>>> FFALIGN(avctx->width, 32),
>>> +
>>> FFALIGN(avctx->width, 16),
>>>
>>> avctx->height, 1);
>>> } else {
>>> context->is_lt_16bpp = av_get_bits_per_pixel(desc) == 16 &&
>>> avctx->bits_per_coded_sample && avctx->bits_per_coded_sample < 16;
>>> @@ -175,7 +179,7 @@ static int raw_decode(AVCodecContext *avctx, void
>>> *data, int *got_frame,
>>> if (context->frame_size < 0)
>>> return context->frame_size;
>>>
>>> - need_copy = !avpkt->buf || context->is_1_2_4_bpp ||
>>> context->is_yuv2 || context->is_lt_16bpp;
>>> + need_copy = !avpkt->buf || context->is_1_2_4_8_bpp ||
>>> context->is_yuv2 || context->is_lt_16bpp;
>>>
>>> frame->pict_type = AV_PICTURE_TYPE_I;
>>> frame->key_frame = 1;
>>> @@ -202,39 +206,65 @@ static int raw_decode(AVCodecContext *avctx,
>>> void *data, int *got_frame,
>>> if (!frame->buf[0])
>>> return AVERROR(ENOMEM);
>>>
>>> - // 1 bpp raw in mov, and 2 or 4 bpp raw in avi/mov
>>> - if (context->is_1_2_4_bpp) {
>>> - int i;
>>> + // 1, 2, 4 and 8 bpp raw in avi/mov
>>> + if (context->is_1_2_4_8_bpp) {
>>> + int i, j, row_pix = 0;
>>> uint8_t *dst = frame->buf[0]->data;
>>> buf_size = context->frame_size - AVPALETTE_SIZE;
>>> - if (avctx->bits_per_coded_sample == 4) {
>>> - for (i = 0; 2 * i + 1 < buf_size && i<avpkt->size; i++) {
>>> - dst[2 * i + 0] = buf[i] >> 4;
>>> - dst[2 * i + 1] = buf[i] & 15;
>>> + if (avctx->bits_per_coded_sample == 8) {
>>> + for (i = 0, j = 0; j < buf_size && i<avpkt->size; i++,
>>> j++) {
>>> + dst[j] = buf[i];
>>> + row_pix++;
>>> + if (row_pix == avctx->width) {
>>> + i += avpkt_stride - (i % avpkt_stride) - 1;
>>> + j += 16 - (j % 16) - 1;
>>> + row_pix = 0;
>>> + }
>>> + }
>>> + } else if (avctx->bits_per_coded_sample == 4) {
>>> + for (i = 0, j = 0; 2 * j + 1 < buf_size &&
>>> i<avpkt->size; i++, j++) {
>>> + dst[2 * j + 0] = buf[i] >> 4;
>>> + dst[2 * j + 1] = buf[i] & 15;
>>> + row_pix += 2;
>>> + if (row_pix >= avctx->width) {
>>> + i += avpkt_stride - (i % avpkt_stride) - 1;
>>> + j += 8 - (j % 8) - 1;
>>> + row_pix = 0;
>>> + }
>>> }
>>> - linesize_align = 8;
>>
>> decreasing linesize_align below the SIMD register size is undesirable
>> as it could lead to unaligned accesses in subsequent code using
>> the frames which would cause speedloss
>>
>>
>
> I haven't decreased anything, rather increased it from previous 4 and
> 8-byte line alignments to 16 bytes. Or do you want me to use 32-byte
> alignment? That's a lot of overhead. And please read your mail.
>
> Mats
>
> _______________________________________________
> ffmpeg-devel mailing list
> ffmpeg-devel at ffmpeg.org
> http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
Please note the the above line is *removing* the "linesize_align = 8*,
not adding.
Mats
--
Mats Peterson
http://matsp888.no-ip.org/~mats/
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