avconv: What are the mpegvideo private options? I'm using avconv on LinuxMint 17.3 to convert video.

The avconv man page states for multiple options, that they are "Deprecated, use mpegvideo private options instead"

Can someone tell me what these private options are and where they are documented?

I noticed that the WinFF program uses -flags +cbp but I don't know what +cbp does or what the equivalent might be. Can anyone enlighten me or point me to more detailed documentation.

Thanks
Private options are switches/flags only applicable to specific encoders or decoders, and ignored by anything else.

To see the available private options for an encoder, use avconv -h encoder=name e.g. avconv -h encoder=flv

For LibAV, these are the private options available for the MPEG-1 &amp; 2 encoders.

{ "mpv_flags",      "Flags common for all mpegvideo-based encoders.", FF_MPV_OFFSET(mpv_flags), AV_OPT_TYPE_FLAGS, { .i64 = 0 }, INT_MIN, INT_MAX, FF_MPV_OPT_FLAGS, "mpv_flags" },\
{ "skip_rd",        "RD optimal MB level residual skipping", 0, AV_OPT_TYPE_CONST, { .i64 = FF_MPV_FLAG_SKIP_RD },    0, 0, FF_MPV_OPT_FLAGS, "mpv_flags" },\
{ "strict_gop",     "Strictly enforce gop size",             0, AV_OPT_TYPE_CONST, { .i64 = FF_MPV_FLAG_STRICT_GOP }, 0, 0, FF_MPV_OPT_FLAGS, "mpv_flags" },\
{ "qp_rd",          "Use rate distortion optimization for qp selection", 0, AV_OPT_TYPE_CONST, { .i64 = FF_MPV_FLAG_QP_RD },  0, 0, FF_MPV_OPT_FLAGS, "mpv_flags" },\
{ "cbp_rd",         "use rate distortion optimization for CBP",          0, AV_OPT_TYPE_CONST, { .i64 = FF_MPV_FLAG_CBP_RD }, 0, 0, FF_MPV_OPT_FLAGS, "mpv_flags" },\
{ "naq",            "normalize adaptive quantization",                   0, AV_OPT_TYPE_CONST, { .i64 = FF_MPV_FLAG_NAQ },    0, 0, FF_MPV_OPT_FLAGS, "mpv_flags" },\
{ "mv0",            "always try a mb with mv=&lt;0,0&gt;",                     0, AV_OPT_TYPE_CONST, { .i64 = FF_MPV_FLAG_MV0 },    0, 0, FF_MPV_OPT_FLAGS, "mpv_flags" },\
{ "luma_elim_threshold",   "single coefficient elimination threshold for luminance (negative values also consider dc coefficient)",\
                                                                      FF_MPV_OFFSET(luma_elim_threshold), AV_OPT_TYPE_INT, { .i64 = 0 }, INT_MIN, INT_MAX, FF_MPV_OPT_FLAGS },\
{ "chroma_elim_threshold", "single coefficient elimination threshold for chrominance (negative values also consider dc coefficient)",\
                                                                      FF_MPV_OFFSET(chroma_elim_threshold), AV_OPT_TYPE_INT, { .i64 = 0 }, INT_MIN, INT_MAX, FF_MPV_OPT_FLAGS },\
{ "quantizer_noise_shaping", NULL,                                  FF_MPV_OFFSET(quantizer_noise_shaping), AV_OPT_TYPE_INT, { .i64 = 0 },       0, INT_MAX, FF_MPV_OPT_FLAGS },\
{ "error_rate", "Simulate errors in the bitstream to test error concealment.",                                                                                                  \
                                                                    FF_MPV_OFFSET(error_rate),              AV_OPT_TYPE_INT, { .i64 = 0 },       0, INT_MAX, FF_MPV_OPT_FLAGS },\
{"qsquish", "how to keep quantizer between qmin and qmax (0 = clip, 1 = use differentiable function)",                                                                          \
                                                                    FF_MPV_OFFSET(rc_qsquish), AV_OPT_TYPE_FLOAT, {.dbl = 0 }, 0, 99, FF_MPV_OPT_FLAGS},                        \
{"rc_qmod_amp", "experimental quantizer modulation",                FF_MPV_OFFSET(rc_qmod_amp), AV_OPT_TYPE_FLOAT, {.dbl = 0 }, -FLT_MAX, FLT_MAX, FF_MPV_OPT_FLAGS},           \
{"rc_qmod_freq", "experimental quantizer modulation",               FF_MPV_OFFSET(rc_qmod_freq), AV_OPT_TYPE_INT, {.i64 = 0 }, INT_MIN, INT_MAX, FF_MPV_OPT_FLAGS},             \
{"rc_eq", "Set rate control equation. When computing the expression, besides the standard functions "                                                                           \
          "defined in the section 'Expression Evaluation', the following functions are available: "                                                                             \
          "bits2qp(bits), qp2bits(qp). Also the following constants are available: iTex pTex tex mv "                                                                           \
          "fCode iCount mcVar var isI isP isB avgQP qComp avgIITex avgPITex avgPPTex avgBPTex avgTex.",                                                                         \
                                                                    FF_MPV_OFFSET(rc_eq), AV_OPT_TYPE_STRING,                           .flags = FF_MPV_OPT_FLAGS },            \
{"rc_init_cplx", "initial complexity for 1-pass encoding",          FF_MPV_OFFSET(rc_initial_cplx), AV_OPT_TYPE_FLOAT, {.dbl = 0 }, -FLT_MAX, FLT_MAX, FF_MPV_OPT_FLAGS},       \
{"rc_buf_aggressivity", "currently useless",                        FF_MPV_OFFSET(rc_buffer_aggressivity), AV_OPT_TYPE_FLOAT, {.dbl = 1.0 }, -FLT_MAX, FLT_MAX, FF_MPV_OPT_FLAGS}, \
{"border_mask", "increase the quantizer for macroblocks close to borders", FF_MPV_OFFSET(border_masking), AV_OPT_TYPE_FLOAT, {.dbl = 0 }, -FLT_MAX, FLT_MAX, FF_MPV_OPT_FLAGS},    \
{"lmin", "minimum Lagrange factor (VBR)",                           FF_MPV_OFFSET(lmin), AV_OPT_TYPE_INT, {.i64 =  2*FF_QP2LAMBDA }, 0, INT_MAX, FF_MPV_OPT_FLAGS },            \
{"lmax", "maximum Lagrange factor (VBR)",                           FF_MPV_OFFSET(lmax), AV_OPT_TYPE_INT, {.i64 = 31*FF_QP2LAMBDA }, 0, INT_MAX, FF_MPV_OPT_FLAGS },            \
{"ibias", "intra quant bias",                                       FF_MPV_OFFSET(intra_quant_bias), AV_OPT_TYPE_INT, {.i64 = FF_DEFAULT_QUANT_BIAS }, INT_MIN, INT_MAX, FF_MPV_OPT_FLAGS },   \
{"pbias", "inter quant bias",                                       FF_MPV_OFFSET(inter_quant_bias), AV_OPT_TYPE_INT, {.i64 = FF_DEFAULT_QUANT_BIAS }, INT_MIN, INT_MAX, FF_MPV_OPT_FLAGS },   \
{"rc_strategy", "ratecontrol method",                               FF_MPV_OFFSET(rc_strategy), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, 1, FF_MPV_OPT_FLAGS },   \
{"motion_est", "motion estimation algorithm",                       FF_MPV_OFFSET(motion_est), AV_OPT_TYPE_INT, {.i64 = FF_ME_EPZS }, FF_ME_ZERO, FF_ME_XONE, FF_MPV_OPT_FLAGS, "motion_est" },   \
{ "zero", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FF_ME_ZERO }, 0, 0, FF_MPV_OPT_FLAGS, "motion_est" }, \
{ "epzs", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FF_ME_EPZS }, 0, 0, FF_MPV_OPT_FLAGS, "motion_est" }, \
{ "xone", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FF_ME_XONE }, 0, 0, FF_MPV_OPT_FLAGS, "motion_est" }, \
{"b_strategy", "Strategy to choose between I/P/B-frames",           FF_MPV_OFFSET(b_frame_strategy), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, 2, FF_MPV_OPT_FLAGS }, \
{"b_sensitivity", "Adjust sensitivity of b_frame_strategy 1",       FF_MPV_OFFSET(b_sensitivity), AV_OPT_TYPE_INT, {.i64 = 40 }, 1, INT_MAX, FF_MPV_OPT_FLAGS }, \
{"brd_scale", "Downscale frames for dynamic B-frame decision",      FF_MPV_OFFSET(brd_scale), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, 3, FF_MPV_OPT_FLAGS }, \
{"skip_threshold", "Frame skip threshold",                          FF_MPV_OFFSET(frame_skip_threshold), AV_OPT_TYPE_INT, {.i64 = 0 }, INT_MIN, INT_MAX, FF_MPV_OPT_FLAGS }, \
{"skip_factor", "Frame skip factor",                                FF_MPV_OFFSET(frame_skip_factor), AV_OPT_TYPE_INT, {.i64 = 0 }, INT_MIN, INT_MAX, FF_MPV_OPT_FLAGS }, \
{"skip_exp", "Frame skip exponent",                                 FF_MPV_OFFSET(frame_skip_exp), AV_OPT_TYPE_INT, {.i64 = 0 }, INT_MIN, INT_MAX, FF_MPV_OPT_FLAGS }, \
{"skip_cmp", "Frame skip compare function",                         FF_MPV_OFFSET(frame_skip_cmp), AV_OPT_TYPE_INT, {.i64 = FF_CMP_DCTMAX }, INT_MIN, INT_MAX, FF_MPV_OPT_FLAGS, "cmp_func" }, \
{"sc_threshold", "Scene change threshold",                          FF_MPV_OFFSET(scenechange_threshold), AV_OPT_TYPE_INT, {.i64 = 0 }, INT_MIN, INT_MAX, FF_MPV_OPT_FLAGS }, \
{"noise_reduction", "Noise reduction",                              FF_MPV_OFFSET(noise_reduction), AV_OPT_TYPE_INT, {.i64 = 0 }, INT_MIN, INT_MAX, FF_MPV_OPT_FLAGS }, \
{"mpeg_quant", "Use MPEG quantizers instead of H.263",              FF_MPV_OFFSET(mpeg_quant), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, 1, FF_MPV_OPT_FLAGS }, \
{"ps", "RTP payload size in bytes",                             FF_MPV_OFFSET(rtp_payload_size), AV_OPT_TYPE_INT, {.i64 = 0 }, INT_MIN, INT_MAX, FF_MPV_OPT_FLAGS }, \
{"mepc", "Motion estimation bitrate penalty compensation (1.0 = 256)", FF_MPV_OFFSET(me_penalty_compensation), AV_OPT_TYPE_INT, {.i64 = 256 }, INT_MIN, INT_MAX, FF_MPV_OPT_FLAGS }, \
{"mepre", "pre motion estimation", FF_MPV_OFFSET(me_pre), AV_OPT_TYPE_INT, {.i64 = 0 }, INT_MIN, INT_MAX, FF_MPV_OPT_FLAGS }, \